Multi-voice input, drum staff and piano roll (and yes I'm talking about 4.5)

[ShibuyaCyana]

MuseScore has 4 voices per staff, but percussion staves, like a regular drum set, are equivalently having a dozen of voices - aka instruments, all cramped into two voices within a single staff. MuseScore is blazing fast in a one-voice-per-staff scenario, but slows down greatly when dealing with multiple voices (e.g. Bach on piano). This percussion problem made it even worse.

Say I want to make some simple backbeat like this:

I type A-B-A-B. With our new percussion system (thank goodness for this update), now we're having something like this:

Then I move my cursor back to the first beat and enter these hi-hats:

... which doesn't work.

I'm not a drummer. Maybe drummers would think the snares and hats on beat 2 and 4 as two "chords". You can argue it's more correct, but to me, it's very counterintuitive if I can't just type the instrument I'd like to hear one by one (and worry about LRLR problem later).

That's why I think there should be a note input mode ¹⁾ called overdub, in which mode when you add a new note to an existing voice, it doesn't cut all other notes off, but automatically form a tied chord with each other, just like how we can easily overdub midi in a piano roll. Like this:

... but it won't completely solve the problem. If the hypothetical overdub mode exists, without other changes, the previous backbeat example would become this:

¹⁾ I realize it's more like a staff / instrument state, or property. It won't change how people type note into the score, but affect how new note interact with existing ones. And there are quite some monophonic instruments that would never use this mode.
Also see #16925 for possible other "modes" designed for piano roll.

This suggests the percussion instruments are fundamentally different from the melodic ones - they only care about where the note starts, not where it ends. Again, in most piano-roll-based software, there's a percussion display mode which completely ignores note length information:

And I can really lay out drums ten times faster in my DAW than in MuseScore. Think of a drum fill like this:

I have to think of drum "chords" and make numerous adjustment of note durations in the same time to finish these two bars; it's like writing an article, but only allowed typing letters column by column, rather than word by word. But it's actually carrying the same information as these triangles:

I could just click the grid, not having to worry about duration problems, or notes in the same voice overwriting each others. It takes less than 30 seconds. What if we can get the same speed in MuseScore?

Bonus:
For those who also struggle with multi voice entering (especially piano), this kind of voice switching is already doable in 4.4, thanks to this PR. It won't automatically fill the rest, and doesn't work across staves, though.