I like the gameboy aesthetic, and the main character looks cool, so I think you're on the right track with the appeal you're going for.
I did have a lot of trouble getting into this one because of the controls and how hard it starts out. I feel like I start out too slow, I get swarmed too quickly, I have trouble aiming, and I don't really get a chance to learn how to play before I'm dead again. I think it'll make a huge difference if you let the player learn the controls in a safer environment before you turn up the heat.
I like the idea of the incremental game loop, I think this could be neat a game, it just needs some more work on the early game to help players get into it.