With these buffs, would the Storm Sorcery subclass still be balanced with other official sorcerer subclasses?

Question

The Storm Sorcery subclass (SCAG, p. 137; XGtE, p. 51-52) is widely regarded as the weakest of the sorcerer subclasses; for instance, see RPGBOT's assessment of the subclass. We - as in my D&D group - mainly play without multiclassing, so combinations like this cleric/sorcerer multiclass build don't help the problem.

To buff the class, I thought of making the following changes:

1. Include the casting of cantrips for triggering the 1st-level Tempestous Magic feature
2. Include the casting of cantrips with lightning/thunder effects for triggering the 6th-level Heart of the Storm feature

This would synergize especially with the thunderclap cantrip:

You create a burst of thunderous sound that can be heard up to 100 feet away. Each creature within range, other than you, must make a Constitution saving throw or take 1d6 thunder damage.

Is the Storm Sorcery subclass with this buff still balanced, especially compared to the other official sorcerer subclasses?

Answer 1

This change is balanced, probably still weaker than other subclasses.

1. Tempestuous magic for cantrips.

This is barely an improvement, in my estimation. This answer soundly reasons that this feature cannot be used as a functional fly speed. The proposed change just takes away the resource expenditure associated with it. It seems to me its equivalent to "+10 feet to your high jump".

To compare to other sorcerers, note the Divine Soul sorcerer's Otherworldly Wings feature:

Starting at 14th level, you can use a bonus action to manifest a pair of spectral wings from your back. While the wings are present, you have a flying speed of 30 feet. The wings last until you’re incapacitated, you die, or you dismiss them as a bonus action.

This probably isn't a good comparison as Otherworldly Wings is superior in every way (which it should be as a 14th level feature), but this change to Tempestuous Magic is very lack-luster.

2. Heart of the Storm for cantrips.

This is very similar to the evocation wizard's potent cantrip and empowered evocation abilities, but limited to a 10 foot area around you.

To compare to a sorcerer, this change basically brings it up to par with the Draconic Bloodline sorcerer's Elemental Affinity ability, but is again limited to a 10 foot area around you.

3. Conclusion.

Overall, I'd say this is balanced compared to the other classes, maybe even still a little weaker. These changes give the storm sorcerer a bit more utility and a bit more damage output, something it lacked compared to the other subclasses, and it does so in a way that doesn't "step on the toes", so to speak, of the other subclasses. The way it gains thematically similar features to those other subclasses is still somewhat unique, and mechanically, isn't quite as powerful as those comparable features. I'd say this almost brings the storm sorcerer up to par with the other sorcerer subclasses.