The concept is really good ! For me, it's a really good foundation for a bigger game, it just need a little bit of polish : cleaner movement (it was a bit frustrating to have to spam A and D to move, and the "character" could go a little bit faster), and, as some other have mentionned, a rotation preview (but I understood that you planned to do it, but couldn't due to time : that's ok, you got the right game-design spirit !).
Otherwise, I loved your idea, good job !