On demand keyboard focus indicator for all monitors?

Question

Is there a way in Windows to indicate on all displays which window|process has the keyboard focus, only on demand by a keyboard shortcut?

(For example with a bigger and centered visual indicator (per display) with the icon and the title, or perhaps mask-coloring all displays with the active app standing out.)

My problem is that when needed to task-switch with many programs (or have focus-stealing ones), I often get slightly distracted from work continuously which over time gets irritating.

How does one lose the focus?

• Windows has allowed focus stealing by default
• even when setting the TweakUI setting, some application manage to steal it
• some always-on-top applications ruin the task-switch list by racing as the first or second list element
• and the MRU algorithm of task switching does not always work for me intuitively when working with more than 2 programs (it's more like vice versa, actually)

Why I just not use the taskbar? I find it less than optimal for several reasons, all of which actually distracts me slightly from working. As I need to find the focus often (working with 3+ applications), the constant slight simulation is actually irritating. The reasons:

• the taskbar is not featured on each display by default
• it lists all running applications, one needs to "parse" it to find the single relevant one
• even if the indicator color would stand out, it's position still dynamically changes
• it is either using up too much screen space constantly (most of the time for no reason) or is too small to spot the current app in optimal time. This can a problem with smaller monitors.
• it can be set to dynamically hidden, but that can be distracting. If unintentionally evoked and/or slow when evoked on purpose (some versions even featuring the resizing of the desktop space which is quite distracting)

(The "activation by keyboard shortcut" method would be optimal for minimizing distraction time for keyboard-heavy workflows.)

I think these are general UX problems and a simple alternative focus visualizer could help them.