A is 10, so it makes sense. Does it go up to F? hmm what would 9999 be under binarywise. Would the most you could get be F999? That would be really neat.
(after playing several battles, I realized that maria had an open slot, so I gave her the aegis shield, immediately after she gained two points in agility x.x; It seems to coincide with monsters running away. also raising HP is slow raising MP isn't too bad, at least not for maria xD)