Hey! A fellow Gamemaker:Studio user. I've tried your game and its Pretty good. Although there are some points this thing could use improvement on. those points are:
1.Enemys are kina scarce, would be nice if they showed up more often.
2.Needs Game feel. Stuff like screen shakes, bright flashes of light, Loud Boom sounds that play whenever you shoot.
3. Could use higher quality sounds
And the points that this just Wins it in are:
Great looking rotation system, Easy Controls, Overall gameplay.
I understand that this is made for a game jam but incase you want to polish it and make it bigger these tips should help. Good luck on your career and in the game jam. and keep up the good work