Old alternate cost idea I had that I'm just going to put here for reference purposes. I plan to expand on it when I have more time, so please ask me before you use it.
Astral :
Astral Energy is not Quanta, but Plasma. Plasma is stored in your mark. Cards that cost Plasma drain it from your mark's current Plasma.
This is intended to create a group of cards that have interesting conversions between Plasma and various Quanta, as well as some original cards of it's own.