Figured I would expand on my RPG fighter a bit, as far as abilities go this is what I am thinking: When you start the game you choose a starting ability.
is Light attack,
is Strong attack, and
is the chosen ability.
can reassigned to any other unlocked ability later, and after a few fights
is unlocked too.
As you level up you can also assign abilities to A+B, B+C, and C+D, for a total of five equipped abilities at a time, and each ability can level up to unlock additional "command abilities" (Think command normals).
General Abilities:
These abilities can be used by any character.
Character Abilities:
These abilities can only be used by specific characters. Note: These are just a few ideas.
Each character can also eventually equip one defense trait and two movement traits. Defense traits are: Parry - with an unlockable Red Parry, Just Defense - with an unlockable "Alpha Counter", and Air Guard - with an unlockable push block. Movement traits include Short Hop, Super Jump, Double Jump, and Wall Jump (There may also be some character specific movement traits such as Wall Cling).
There are also "Burst" abilities that can be equipped to A+B+C and B+C+D that are largely class specific and permanently consume your super gauge, much like Samurai Showdown.
TL;DR: I am mildly obsessive and have thought about this WAY too much.