I have been playing around in the level editor recently, and have noticed some annoying/inconsistant things that could use improvement in order of annoyance.
1) placement surfaces cant be rotated
2) Set the X rotation to 90 or 270, and then set the Z rotaiton to be non 0, causes the object to spin around
3) Set the X rotation to 88 (or other values near 90 or 270), click out of the edit menu, click the block again, and the X rotation is 90, select the X rotaiton, and the block visible shifts (an X rotation of 88 is possible, but the GUI does not think that is should be)
4) Tab goes to the next box in the menu, and shift-tab goes to the previous but also brings up the overlay
5) Tab does not go to any box in the menu if none are selected, similarly, ctrl-d (duplicate) does not duplicate if any box in the menu is selected