It would be handy to be able to UNDO several steps at a time, and also to know to which exact step to undo. If the Undo button could show a list of steps, say at least the last 20 changes I made, then I could select from it how far back I want to undo, and get the "undoing" done in one click. Right now it often takes a long time to undo something, if I, say, make a few changes just to try out some particular thing, do a few things on the timeline... and then decide it won't work. Some other programs have this feature and in them, I really appreciate it.