Developing new subclass system

I have added a new subclass system where you can add 2 sub-classes per character. I have added a new menu item called Souls, to hold this. The sub-menu works quite well, correctly showing all stat changes when equipping/unequipping/changing a soul (read: class). 

Each soul has their own, currently working leveling system in conjunction with the character's class. It has stats (hp, mp, atk, def, matk, mdef, agi, luck) that adds to the character when equipped, much like equipment. Each soul has it's own level and experience value, and as the level goes up, the stat increase of the item goes up (quite intuitively). 

Each soul also has a set of skills that it will learn as that soul gains a level. A character who has a soul equipped will learn the skills of the soul it has equipped. Note that a soul can freely be changed around as it keeps its level even when unequipped. 

This feature leads to another big feature: 

Tiered skills. If a character equips a soul who has the same skill as that character already knows, either innately or from another soul, the already known skill is replaced by a new, stronger version of that skill. Similarly, if a character unequips a soul which has a skill, that skill is forgotten or downgraded. There are three tiers; a base one, a stronger one, and an ultimate one. 

Three things remains to do here; 

One - add mechanism for gaining new souls.  The blueprints for this is more or less clear, but unimplemented, and will largely be related to defeating enemies in a certain way. 

Two - add the souls themselves, one per defeatable enemy. The big part of work here is to balance the available skills and stats per soul.

Three - add three tiers for every new skill. The skills already in the game per now have working tiered skills.