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Though your question is written in a slightly confusing fashion and seems to assume a simplistic view of the concept of hyperconjugation, I will try to answer to "If hyperconjugation should be more seen as a more delocalized phenomenon, would distance and geometry play such important factors?". IT DEPENDS on the specific case. However, from fundamental principles, distance and geometry are the critical factors in all types of interactions involving charge transfer, including hyperconjugation, irrespective of the magnitude of the interaction in a particular case. [1] Delocalization of electrons itself is caused both by distance and geometrical factors. Orbital sizes are defined finitely; thus correct donor-acceptor distances are crucial for orbitals to be able to overlap or hybridize. In most cases, a proper orbital distance (assuming an adequate symmetry, see below) is proportional to the stabilization energy that is achieved, with the concomitant delocalization of the electron or electrons (double hyperconjugation). [2] Of course, geometry (topology, technically) is just as crucial, because if the donor and acceptor orbitals are not allowed to overlap in space by symmetry, then no 'hyperconjugative stabilization' is likely to occur (perhaps other types of factors, stabilizing in some cases, such as exchange repulsions from the periphery, and/or Coulombic factors, could, directly or indirectly, create the illusory picture that the system is somehow stabilized hyperconjugatively, even though no geometrically correct orbital matching was even there. This all, adds to the complexity of dissecting energy contributions accurately, even for 'simple' molecular systems). Going back to the dynamic nature of hyperconjugation, and to your question on the importance of the degree of localization or delocalization in defining the mere concept, in [3], it was found that hyperconjugative and not steric reasons are behind the preference of ethane to adopt a staggered conformation over an eclipsed one; it was found explicitly that vicinal hyperconjugation (σCH–σCH*) and not geminal hyperconjugation (σCC–σCC*) factors lead to the staggered equilibrium structure of ethane. On the other hand, and as a contrasting example, in [4], it is geminal hyperconjugation which is linked to the low ring strain of cyclopropane, and not vicinal. The views expressed in [3] are disputed in [5]. Based on these two examples, it seems as if tight, or strained hydrocarbon species in space, and hindered small systems, display a more "localized" type of hyperconjugation, semantically speaking, hence favoring geminal hyperconjugation, whereas relaxed systems may prefer vicinal hyperconjugation. These are just two basic examples I could pick out from the literature and which you can use with those you already asked and were answered by Gwendal to increase your intuition about the phenomenon, but eventually, you will realize that these stabilizing interactions are not detectable quantities, and thus it is impossible to define them or generalize cases wholly from basic concepts or from hardcore quantum chemical methods, at the moment. Keep in mind that hyperconjugation is a highly controversial topic, all the way from the days of Mulliken and Dewar [6,7]. A comprehensive review [8] may help out.

References.

1. M. Solà, Frontiers in Chemistry 2017, 5.
2. I. Judy, C. Wu, P. von Ragué Schleyer, Pure and Applied Chemistry 2013, 85, 921-940.
3. V. Pophristic, L. Goodman, Nature 2001, 411, 565.
4. S. Inagaki, Y. Ishitani, T. Kakefu, J. Am. Chem. Soc. 1994, 116, 5954-5958.
5. F. M. Bickelhaupt, E. J. Baerends, Angew. Chem. Int. Ed. 2003, 42, 4183-4188.
6. a) R. S. Mulliken, J. Chem. Phys 1939, 7, 339-352. b) R. S. Mulliken, C. A. Rieke, W. G. Brown, J. Am. Chem. Soc. 1941, 63, 41-56.
7. M. J. S. Dewar, H. N. Schmeising, Tetrahedron 1959, 5, 166-178.
8. I. V. Alabugin, K. M. Gilmore, P. W. Peterson, Wiley interdisciplinary reviews: computational molecular science 2011, 1, 109-141.

Though your question is written in a slightly confusing fashion and seems to assume a simplistic view of the concept of hyperconjugation, I will try to answer to "If hyperconjugation should be more seen as a more delocalized phenomenon, would distance and geometry play such important factors?". IT DEPENDS on the specific case. However, from fundamental principles, distance and geometry are the critical factors in all types of interactions involving charge transfer, including hyperconjugation, irrespective of the magnitude of the interaction in a particular case.^[1] Delocalization of electrons itself is caused both by distance and geometrical factors. Orbital sizes are defined finitely; thus correct donor-acceptor distances are crucial for orbitals to be able to overlap or hybridize. In most cases, a proper orbital distance (assuming an adequate symmetry, see below) is proportional to the stabilization energy that is achieved, with the concomitant delocalization of the electron or electrons (double hyperconjugation).^[2] Of course, geometry (topology, technically) is just as crucial, because if the donor and acceptor orbitals are not allowed to overlap in space by symmetry, then no 'hyperconjugative stabilization' is likely to occur (perhaps other types of factors, stabilizing in some cases, such as exchange repulsions from the periphery, and/or Coulombic factors, could, directly or indirectly, create the illusory picture that the system is somehow stabilized hyperconjugatively, even though no geometrically correct orbital matching was even there. This all, adds to the complexity of dissecting energy contributions accurately, even for 'simple' molecular systems). Going back to the dynamic nature of hyperconjugation, and to your question on the importance of the degree of localization or delocalization in defining the mere concept, it was found that hyperconjugative and not steric reasons are behind the preference of ethane to adopt a staggered conformation over an eclipsed one;^[3] it was found explicitly that vicinal hyperconjugation (σCH–σCH*) and not geminal hyperconjugation (σCC–σCC*) factors lead to the staggered equilibrium structure of ethane. On the other hand, and as a contrasting example, it is geminal hyperconjugation which is linked to the low ring strain of cyclopropane, and not vicinal.^[4] The views expressed in ref. 3 are, however, disputed by Bickelhaupt and Baerends.^[5] Based on these two examples, it seems as if tight, or strained hydrocarbon species in space, and hindered small systems, display a more "localized" type of hyperconjugation, semantically speaking, hence favoring geminal hyperconjugation, whereas relaxed systems may prefer vicinal hyperconjugation. These are just two basic examples I could pick out from the literature and which you can use with those you already asked and were answered by Gwendal to increase your intuition about the phenomenon, but eventually, you will realize that these stabilizing interactions are not detectable quantities, and thus it is impossible to define them or generalize cases wholly from basic concepts or from hardcore quantum chemical methods, at the moment. Keep in mind that hyperconjugation is a highly controversial topic, all the way from the days of Mulliken and Dewar.^[6–8] A comprehensive review may help out.^[9]

References

1. Solà, M. Why Aromaticity Is a Suspicious Concept? Why? Front. Chem. 2017, 5, 22. DOI: 10.3389/fchem.2017.00022.

2. Wu, J. I.; Schleyer, P. v. R. Hyperconjugation in hydrocarbons: Not just a “mild sort of conjugation”. Pure Appl. Chem. 2013, 85 (5), 921–940. DOI: 10.1351/PAC-CON-13-01-03.

3. Pophristic, V.; Goodman, L. Hyperconjugation not steric repulsion leads to the staggered structure of ethane. Nature 2001, 411 (6837), 565–568. DOI: 10.1038/35079036.

4. Inagaki, S.; Ishitani, Y.; Kakefu, T. Geminal Delocalization of .sigma.-Electrons and Ring Strains. J. Am. Chem. Soc. 1994, 116 (13), 5954–5958. DOI: 10.1021/ja00092a052.

5. Bickelhaupt, F. M.; Baerends, E. J. The Case for Steric Repulsion Causing the Staggered Conformation of Ethane. Angew. Chem. Int. Ed. 2003, 42 (35), 4183–4188. DOI: 10.1002/anie.200350947.

6. Mulliken, R. S. Intensities of Electronic Transitions in Molecular Spectra IV. Cyclic Dienes and Hyperconjugation. J. Chem. Phys. 1939, 7 (5), 339–352. DOI: 10.1063/1.1750446.

7. Mulliken, R. S.; Rieke, C. A.; Brown, W. G. Hyperconjugation. J. Am. Chem. Soc. 1941, 63 (1), 41–56. DOI: 10.1021/ja01846a008.

8. Dewar, M.; Schmeising, H. A re-evaluation of conjugation and hyperconjugation: The effects of changes in hybridisation on carbon bonds. Tetrahedron 1959, 5 (2-3), 166–178. DOI: 10.1016/0040-4020(59)80102-2.

9. Alabugin, I. V.; Gilmore, K. M.; Peterson, P. W. Hyperconjugation. Wiley Interdiscip. Rev.: Comput. Mol. Sci. 2011, 1 (1), 109–141. DOI: 10.1002/wcms.6.

Though your question is written in a slightly confusing fashion and seems to assume a simplistic view of the concept of hyperconjugation, I will try to answer to "If hyperconjugation should be more seen as a more delocalized phenomenon, would distance and geometry play such important factors?". IT DEPENDS on the specific case. However, from fundamental principles, distance and geometry are the critical factors in all types of interactions involving charge transfer, including hyperconjugation, irrespective of the magnitude of the interaction in a particular case. [1] Delocalization of electrons itself is caused both by distance and geometrical factors. Orbital sizes are defined finitely; thus correct donor-acceptor distances are crucial for orbitals to be able to overlap or hybridize. In most cases, a proper orbital distance (assuming an adequate symmetry, see below) is proportional to the stabilization energy that is achieved, with the concomitant delocalization of the electron or electrons (double hyperconjugation). [2] Of course, geometry (topology, technically) is just as crucial, because if the donor and acceptor orbitals are not allowed to overlap in space by symmetry, then no 'hyperconjugative stabilization' is likely to occur (perhaps other types of stabilizing factors such as exchange repulsions from the periphery, and/or Coulombic factors, could, directly or indirectly, create an illusory, hyperconjugative donor-acceptor system, in which no geometrical orbital matching was spatially conceivable, adding to the confusion). Going back to the dynamic nature of hyperconjugation, and to your question on the importance of the degree of localization or delocalization in defining it, in [3] it was found that hyperconjugative and not steric reasons are behind the preference of ethane to adopt a staggered conformation over an eclipsed one; it was found explicitly that vicinal hyperconjugation (σCH–σCH*) and not geminal hyperconjugation (σCC–σCC*) factors lead to the staggered equilibrium structure of ethane. On the other hand, in [4], it is geminal hyperconjugation which is linked to the low ring strain of cyclopropane. This view is disputed in [5]. It seems as if tight spaces or strained, and hindered small systems, display a more "localized" hyperconjugation, semantically speaking, and favor geminal hyperconjugation, whereas relaxed systems may prefer vicinal hyperconjugation. These are just two basic examples I could pick out from the literature and which you can use with those you already asked and were answered by Gwendal to increase your intuition about the phenomenon, but eventually, you will realize that it is not a detectable quantity and thus it is impossible to define wholly from basic concepts. Keep in mind that hyperconjugation is a highly controversial topic, all the way from the days of Mulliken and Dewar [6,7]. A comprehensive review [8] may help out.

Though your question is written in a slightly confusing fashion and seems to assume a simplistic view of the concept of hyperconjugation, I will try to answer to "If hyperconjugation should be more seen as a more delocalized phenomenon, would distance and geometry play such important factors?". IT DEPENDS on the specific case. However, from fundamental principles, distance and geometry are the critical factors in all types of interactions involving charge transfer, including hyperconjugation, irrespective of the magnitude of the interaction in a particular case. [1] Delocalization of electrons itself is caused both by distance and geometrical factors. Orbital sizes are defined finitely; thus correct donor-acceptor distances are crucial for orbitals to be able to overlap or hybridize. In most cases, a proper orbital distance (assuming an adequate symmetry, see below) is proportional to the stabilization energy that is achieved, with the concomitant delocalization of the electron or electrons (double hyperconjugation). [2] Of course, geometry (topology, technically) is just as crucial, because if the donor and acceptor orbitals are not allowed to overlap in space by symmetry, then no 'hyperconjugative stabilization' is likely to occur (perhaps other types of factors, stabilizing in some cases, such as exchange repulsions from the periphery, and/or Coulombic factors, could, directly or indirectly, create the illusory picture that the system is somehow stabilized hyperconjugatively, even though no geometrically correct orbital matching was even there. This all, adds to the complexity of dissecting energy contributions accurately, even for 'simple' molecular systems). Going back to the dynamic nature of hyperconjugation, and to your question on the importance of the degree of localization or delocalization in defining the mere concept, in [3], it was found that hyperconjugative and not steric reasons are behind the preference of ethane to adopt a staggered conformation over an eclipsed one; it was found explicitly that vicinal hyperconjugation (σCH–σCH*) and not geminal hyperconjugation (σCC–σCC*) factors lead to the staggered equilibrium structure of ethane. On the other hand, and as a contrasting example, in [4], it is geminal hyperconjugation which is linked to the low ring strain of cyclopropane, and not vicinal. The views expressed in [3] are disputed in [5]. Based on these two examples, it seems as if tight, or strained hydrocarbon species in space, and hindered small systems, display a more "localized" type of hyperconjugation, semantically speaking, hence favoring geminal hyperconjugation, whereas relaxed systems may prefer vicinal hyperconjugation. These are just two basic examples I could pick out from the literature and which you can use with those you already asked and were answered by Gwendal to increase your intuition about the phenomenon, but eventually, you will realize that these stabilizing interactions are not detectable quantities, and thus it is impossible to define them or generalize cases wholly from basic concepts or from hardcore quantum chemical methods, at the moment. Keep in mind that hyperconjugation is a highly controversial topic, all the way from the days of Mulliken and Dewar [6,7]. A comprehensive review [8] may help out.