the game was made with the idea in mind to keep it small and fast (even tho it took almost a year to develop xD), so its definitely a bit rough around the edges. As for how upgrades work, maybe I'll add it to the description how they work, but basically you can chose between a weapon and score +20%, weapons stack meaning if you click boomerang twice for example you'll get 2 boomerangs at once or half the time inbetween boomerang throw.