Feature Addition: Trill Timing Adjustment in Property Editor

I think the Playback should produce an accurate interpretation of the music. I've noticed that MuseScore's playback of the trill is off-putting.
Take for example, this accurately notated Chopin's Nocturn Op. 9 No. 2, bar 7:
https://musescore.com/user/6662591/scores/4383881

The trill sounds terrible. Should be much faster.
I spent a long time perfecting this score with my own version:
https://musescore.com/user/36518770/scores/6473380

But to achieve a properly timed trill, I had to either:
1) add it as a second voice, then hide the notes (which keeps extra space in the bar)
or
2) add it as a second instrument, then hide everything that way (which then shows the score has having 2 instruments, when the second is just a hack to get it to play right)

TL;DR:
It would be better if we could just notate a trill, then use the property editor to adjust how slow or fast the trill should be played.

And while we're adding features to this. A cool extra thing to add would be to make it so the speed of the trill could be variable over the length of the trill as defined by the user.