I could make an edit on an old system I made for an old Persona RP. The way that one worked was based off of logistics in the fighting games, since lower level skills like Garu, Zio and Agi were spammable to infinity.

In that system you had Persona Points, and it would cost 1-3 points depending on the strength of the skill. Like, Garula would be 1 point, Garudyne would be 2 points, and Phanta Rei would be 3 points.

I'm definitely changing the system for this RP since you can't have lower level skills, since I based the way it worked off of advancements in Persona Q.

I might borrow the Brave and Default idea to some degree were I to make a system for this RP.

The problem is getting everyone to suddenly use it, which is why I can't make it too complex, or too dependent on using the system.