This is a pretty crazy thing you are making. You have done so much with it in a small amount of time, yet I still cannot figure out what you are actually going for. It looks like the shotgun is going to be for a lot more than busting through a whole bunch of enemies that are going to make an eventual appearance, but the whole thing feels so suited for a puzzle platformer while the other two games you are working on both seemed like pretty great themes for a roguelike already.
I was too apprehensive about trying to make something for the 7drl, was late to enter, plus it seems like any one I would want to make would wind up taking more than 7 days. (Yeah, I guess I have your problem of needing to be better at making small games. Just seemed like 7drl was too big of a challenge for me on that front.) Can't wait to see how this project turns out!