Welcome to the forum (and I love your name, Thanoseid!)
As for Absorption, it is one of the trickier powers in the game. Even recently (and I've been GMing this game regularly for over 30 years) I've had to work with a couple of PCs in toning down their characters, both as a result of this power.
My simplest recommendations would be:
- Require it to cost an action to absorb (preferably a "saved action" by the character).
- Set hard limits in what can be absorbed (and what happens if that limit is exceded).
- Don't allow this to combo with Heightened Agility or Heightened Speed (which allow for more actions, which lead to abuse).
- Until you've got a great grasp on the game, I'd hold off on allowing the absorption of other super powers. If you do allow it, you might consider limiting it to a single one at a time (to avoid serious power creep).
One of our current PCs started out a character with Absorption that required him to have a saved action or to successfully hit (HTH) with a special attack. This proved too weak, and when he finally returned to playing the character I allowed much more. To date he can hold three super powers, and to give you an idea of how powerful he is, he just chose to drop Power Blast x2 (which started at 2d20 damage).
So it's one of those that you really need to be cautious with. And be careful (like you mention) with the other open-ended powers, too, in combination with it.