MuseScore 3.6/4.0 Wishlist

I've been using MuseScore pretty regularly for the last two years, and getting pretty good at creating elegant scores; but here are a few notational situation that I've found MuseScore has trouble with. I should preface this by saying that these are for the most part notation issues only--although I use playback regularly, I'm less concerned with it, and mainly use MS as a scorewriter. Also, they can all be remedied using adjustments or work-arounds, but they're all become standard notation, and shouldn't require a work-around.

I. Better handling of slur/ties curves--in particular:
--when a notehead is at the terminus of both a tie and a slur, the two often overlap.

 --when a ties/slur crosses a system which ends with a time-signature change, the curve extends to the very end of the staff; it should end at the barline which precedes the new time-signature.

 --laissez vibrer ties/slurs:  there are several ways to create them, all counter-intuitive work-arounds.  Also, a possibilty for realization in playback?

II. Compund time signatures: of the sort "3/4=6/8" or "3/4(6/8)." Simple to notate the rhythms, using beaming and measure properties, but creating the time-signature glyphs themselves is extremely cumbersome.

I expect many, if not all, of these are scheduled to be included in the next version(s); and if not, I hope it's not too late to do so. As always, thank you--

-- WF