Well a no crystarium would probably be all but impossible unless you spend forever leveling up accessories or avoid all mooks and spam eidolons every chance you get, and I doubt even that would be enough to make up for it, since I think without it you can only equip one accessory. FFXIII kinda defies these challenges, huh =p

No Medic or Sentinel? Healing via items only? I dunno, never really been one for challenges anyway.