I took a quick look at staff view today. It's better, maybe, than it used to be, but there is so much that just looks bad. These things are not on your list, but they are what anyone who is accustomed to music scores sees instantly.
Beams: always flat
Enharmonics: frequently wrong, and not easy to change (the only way I found is to call up the Note Properties dialog, highlight the pitch field, and type in the correct name.)
Stem length: for notes with ledger lines, comically short.
Interface things:
-- That flashing thing that shows where your mouse pointer is, in time, notes, and midi number? Good grief. I can see a beginner liking it, but I really do not want a flashing thing that is fixed in place and does not follow the cursor. Could not find a way to disable it.
-- Need the option to have staff names 'float' ... it's completely impractical to go back to the beginning to remind yourself which is the trumpet and which the horn; likewise key signatures and perhaps time signatures need a float option.
More subtle things, one could live with them:
-- Spacing is pretty crude, vertical and horizontal.
-- Combine tracks onto a staff? This may be possible, but I didn't see a way to do it. Very helpful in compressing an instrument, divided up in order to get articulations, but back together for the musical line.
-- "hairpin" the only option for the hundreds of things one might put into a score ..
-- "pedal" for all tracks, even the trumpets and horns?
-- the horizontal band under staves ... is that for placement of dynamics and hairpins? very bad idea. And it appears that once it is put on, it won't go away. Consider this: staff lines are horizontal lines, there are five of them. With those bands, two more are placed in 'ledger-line' area ... making for a very hard to read version of even a simple score.