+1
...maybe a "Q-Tool", not only in the Piano Roll, but also in the main window for processing full clips ?
I used to use "P" in Logic a lot for this sort of manipulation (each clip has its own Q settings and they are non-destructive).
As Parameters can be placed anywhere on the screen, and the window is also shown on the left (always showing the selected clip), it was very easy to Q any sequence within about 1,5 sec, to try and tweak the settings to taste many times, or to revert back to the original, nonquantized clip data at any time.
With a Q-Tool in the main window, with one click we could easily
1) apply last set nondestructive Q settings to a clip,
2) copy Q settings from one clips onto the other,
3) pick one clip as a groove or grid Q pattern for another clip
3) as its non-dectructive, one could only modify some parameters after copying full settings from another clip.
With the Parameter window that appears always near the cursor and always shows the selected clip/clips parameters (handy LINKed window feature), changing the Q settings wouldn't require wide mouse movements = would be very, very quick.
PS. In the "Logic ripping" thread I've just included two screencaps. The first one shows the Parameter window method and shows all its cool Q parameters, all available nondestructively and separate for every clip. ...And you may even select multiple clips, and change any of their parameters in sync (absolutely or relatively)
!