The game is very good and especially very fun. I've had a blast playing this and have even managed to get some good scores. Each of the game-modes bring something unique to the table and are great in different aspects (personally I think the square is the best).
I do think the triangle is a bit overpowered in terms of point collection as I've noticed that I got a lot of points while being in the triangle form.
One issue I'd like to point out is how hard it is to track the player, sometimes it takes me a few seconds to locate it and it's very confusing, I think one solution would be to make the player have a customizable color.
To close off this comment, I think this game is very good and I see a bright future in it, I can definitely see this becoming something decently big in the future if it does get updated, I also think this would go hard on mobile.