If I could recall how to target the last planted brick by a player then this could easy be done, and could overwrite the undo command.
also maybe someone could fix the redo script, I haven't seen much talk about it in a while. It's gotta be possible without being very glitchy by now right? It's at least worth looking into.
Ctrl+z now checks to see if that brick is supporting anything. If so, it deletes the brick rather than killing it.