I've found that users often struggle with getting the vertical boundaries of interior elevations correct and aligned. Currently, they can only be edited manually, by dragging the extent of the crop box around in the elevation. The align tool doesn't work on them.
I'd like to be able to grab a bunch of elevations, and set them numerically. (Just like a wall or any other 3d element.)

The point of this is to keep the elevation views aligned with the floor and the ceiling.
It would also be nice to be able to tell the elevation view to go back to attach to the extents of the room.