Alright, Classes and what makes a class is probably my favorite part of an RPG. And it's most defining quality. Whether it's a character who is obviously that class, or nameless characters and they have classes given, or a class and job system, or a freeclass system, the concept of Class is crucial. @TheWizard
has hinted here and there at what bits and pieces will be the core of the system. I think this is a good place to truly get deep into the nuts and bolts of class dynamics, good classes, bad classes, and what classes should branch from where and why, and what skills should go to what classes and what kinds of armor, equipment and special items potentially and ideas for unique kinds of classes and class mechanics.
I will first pitch the primary question towards Wiz of, any idea of how deep, both vertically and horizontally, the class tree for the classes will be anticipated to be, along with the secondary important question of, will a base class path be locked in place or can one venture from a wizard to a warrior path for a set valuable of some sort? Be it it costs a penalty or it costs gold or w/e.
I'm holding back naturally from going into my wealth of ideas but idealistically I'm thinking you already mentioned a 3 branch system. I'm wondering how many tiers you would be willing to vertically go with that and cross map with it. If you are worried about it on a dynamic level, I can solve that easily. Though programming wise is probably where I feel it might be trickier I assume.
Here is where I feel the big conversation on classes as a whole can be opened up and get really nerdy however.