Hi BlankShade, glad you enjoyed the working part of the game.
We implemented the skill tree and gem part in only 2 hours, and I think it shows a bit, maybe it would have been better to not distract players with it.
In any case, it was only 4 lines of code to adjust the spawn rate and prices, so once votes are in, we will push an update with some hot fixes :D
We will at some point also add invincibility frames, to avoid the double stunning effect.