OK, trying to get an idea how to set up a Level Up table.
Different games do different things on level up.
All games have an experience curve. It's not too important how it is stored; it can be a cumulative amount or an increment from previous. (FF6 acttually only stores increments/8). Either way accomplishes the same thing.
FF1 has HP increases (one of two types, chosen by a bit called 'weak/strong'), stat increases (5 bits, if set the stat increases by 1), and MP charge increases (8 bits, if set the corresponding level charge increases by 1). Each class has its own table of size [MAXLEVEL-1]. I'm not 100% sure, but I believe there are only 6 tables, with promotions still using the same table.
FF6 has HP and MP increases. They do not vary from character to character; everyone has the same Exp requirements and gets the same HP and MP increases. However, the amount to increase HP or MP can be affected by an Esper bonus of some percent, and the 4 base stats of FF6 can be incremented by 1 or 2, again based on an Esper bonus (if equipped).
So, now a quick proposal:
A table, size MAXLEVEL-1, for each class.
Each entry would hold the following (4 bytes each):
1. Exp. needed
2. HP increase (0 or 1, weak or strong level up. This could be defined in other games as a straight increase)
3. MP increase (to use for charges, 4 bits each, gives you 8 levels of magic)
4. Stat increase (to use for the 5 base stats... 4 bits each? Could go as high as 6 bits but that's kinda overkill)
5-32. Padding for chunk, could be defined by other games.