Sometimes you just need to unga bunga and this game gives a lot of good unga bunga.
The good:
Seriously, it the sound effects carry a lot in making this game just feel damn good to play so super props to that. Each different gun has such different, and well placed sound SFX (given the time limit of a game jam) that lets them each be recognisable.
Shooting and killing enemies have so much juice on them, it feels damn good to play.
To improve:
The game is quite good but I think overall engagement could be improved a bit more ie. have a bit more challenge here and there. What if you introduce mini-bosses that don't die as quickly, sporadically? They could spice things up a bit.
Very nice game!