It would be great to have a build floor option (without walls) OR the ability to resize floors without walls because redrawing, resizing walls, and then using the hole tool because you made your lower level 1 block bigger is a lot of effort.
When you drag or move walls (up/down/to the sides) they often lose splits and paint, or they hide columns that were visible (they make that wall “on top”). They should not hide columns unless the wall the column goes into is the one moving. There should be a remove split button and they should not erase themselves. Paint shouldn’t remove (notice this especially on columns) or need to be reapplied if you change a floor color and hid the floor.
If there’s an object in the way you can’t move doors down because it’s “in the way”… (see bricks)…also it force exits build mode if your click releases on the same square as an item (a huge pain).