The setting of Final Fantasy Tactics (Advance) is remarkably compelling from a tabletop standpoint. By suggesting that the party are playing reconstructions of self-characters who can change jobs via equipment, a number of possible games are suggested.
What system can model the "job switching" mechanic of final-fantasy tactics along with the movement and facing elements? What sub-systems do I need to tack on from other games to provide for the psychological "this is a construction from the players' minds" element?
