Yeah I probably played it for over an hour in total. It really starts getting fun when 10 enemies get spawned in at the same time and you have to kill them before they kill you. Still the best game I've played this jam. Also, I was wondering if you played Hotline Miami? I think you'd like it!
HM is fun for some of the same reasons your game is fun: killing enemies before they can react and then using their weapon to kill other enemies. I couldn't recommend it more.
Multiplayer sounds awesome! I'll be there to play it if you decide to add it in.