I like the twist that you are more accurate the more you move.
Maybe have an interval between shots because I felt like I could spam the shots and it removed from the idea of having these quick satisfying precise shots if you know what I mean.
Occasionally one of my plants would be on the edge and a squirrel would come from that same edge, immediately getting away with the plant haha so maybe some way to solve that as it felt a bit unfair. Maybe squirrels can't spawn too close to a plant etc or you have some way of moving the plants?
I think it has room to be built upon like different guns with other weird twists etc could be fun. Nice job!