Makes sense to me! Actually, the way you phrased that made me think of some very different mechanic ideas. The main one is adding some sort of gizmo that moves all your placed keys when you run into it. Something like an arrow that could face up, down, left, or right. That would add lots of possibilities, especially combined with common mechanics like push-able blocks and various sorts of switches. Also, lines of arrows could turn the placed keys into an interesting version of moving platforms.