i just played this today -- this is so much fun. it's kind of everything i'm trying to do to be honest.
the only suggestion i can make is it would be nice if the reticle pushed your camera forward so you can peek around the map. i found myself trying to do that because of enter the gungeon. edit: looks like that's already in the game. i dunno why i didn't notice at first
also, this has the art style (and violent subject matter) that if you posted it to newgrounds, it would guaranteed be front page.