Our current undo feature only un-moves items, un-deletes items, and I think...not too sure about this one....un-changes the size of items. I propose that they make it a building tool that will undo color changes and texture changes. It would be especially helpful for those accidental clicks that turn an entire building into some strange texture like, curtains and then you have to go around and re-texture and color every little piece of the building because you forgot to choose "select individual" or "select texture".
The proposal number is 108