I think it would make more sense as game if you had to one shot different shape of structures and then it would calculate the score how far each one fell from it's original position.
I don't anyone thinks about hexahedrons when hex is mentioned and even less about regular square boxes. Why not hexagonal prisms? Would be cool if smashing two bodies would combine them into one.
Viewing post in Safety Hazard jam comments
I purposefully ruled out hexagons/curses to have some novelty in the mix but the final theme did end up being bit of a stretch. I was working on a fire mechanic for merge where you could knock a flame source into a pile and make it explode but the performance suffered a bit. I like your one shot suggestion, maybe another mode down the line.