Ok, so there are the powers that you need to activate by pressing the up or down arrow, but I think there should be a different type of power. This power would not be activated by you pressing the arrows, but would either always be active, or activated by something else (such as dying or getting your points stolen). Maybe one could make it so you are always 25% smaller or one that makes it so when you die it takes some points from people in a small radius around you. these are just some suggestions of the different type of power, of course someone actually creative unlike me could probably do a better job of coming up with more ideas. I think adding this new power type will make the game a lot better from a customizable gameplay standpoint.
We actually made these once in the prototype, they were called passive powers.
It never made it in the live game because it was hard to balance and come up with a lot of ideas.