It would be nice if you can click on a box to bring it to the front, allowing you to specify the order of boxes. This becomes more important with box backgrounds.
Right now you can’t reorder, so it solely depends on when you create the box. (Not technically true, the workaround is to lock the box, which will send to back).
I realized if a box gets entirely covered by another’s background, you won’t be able to see or manipulated it. Might be better to always keep the box names and borders visible, even if it defies physics?