Very good suggestions! I would like to augment one of yours slightly:
5) Ability to show find in files results in dockable window, instead of just another tab, thereby allowing user to view results while also viewing a document.
Add to this a keystroke that allows you to go to the next item in the “found” list. Kind of like VS does when you have compiler errors and you can move to the next error.
This is a HUGE timesaver!