I know I've suggested a lot of stuff recently, but I think this one is pretty good.
I think it'd be really nice to have a scroll-to-zoom feature in the map editor. This could be off by default, but it'd make it much easier to use. Also, I would like to be able to look around like in normal mode. Of course, this couldn't be on normally, as moving the mouse moves the cursor; there could be a key, though, that when pressed, made mouse movement look around.
Does those sound useful?