I really like generic classes, and I like the idea of moving class powers into feats and feat chains. Ideally one could capture any PrC by creating feat progressions for them.

I don't think that the 3 tiers of the 3 paths with 4 choices is right though, for a few reasons:

I think the number of tiers in any path should be equal to the number of path choices one can make, or it doesn't allow for someone to be fully dedicated to one of the 3 paths.

If you reduce charcters to picking 3 tiers it isn't that bad - you get 9 combinations still, and the combinations that are removed are not necessary;
you still have a jack of all trades (1/1/1), and you have cross classes (2/1 and 1/2) to allow for the caster who fights or the fighter who casts.

Alternatively, increasing the tiers per path to 4 might work.

I'm not sure I like typing HD to BAB to weapon/armour proficiencies all in choosing the path.

I don't think the feats really work the way you have them laid out -

Character classes allow one to bundle good abilities with not so hot stuff, and you need to waste levels picking up things that aren't of much use to be able to get the stuff you want. These llittle abilities are likely not worth putting feats into, but add to the feel of a class (no longer aging as a druid, being able to send an animal messenger as a deepwarden). To solve this kind of thing in a more generic setup, you need to do one of a few things:

* Make all feats equally viable? Not really an option I don't think - higher level feat choices may be impossible to balance with lower ones.

* Have different costs for feats. Is Poison Immunity as good as Power Attack? Cost them differently - this requires breaking up feats though by cost/power, and can get tricky as heck.

* Make feat prequisite chains. I notice you did that in a few places, Poison Immunity as an example, but I think it needs work. I can see why poison immunity might have feat prerequisites, but less so why anyone would bother to follow them. Only if Poison Immunity were required for Greater Wild SHape or something can I see someone bothering to pick it up. While I understand making the wildshaping feats rely on the earlier wild shaping feats (sensible), if you don't pair weak feats as prerequisites to stronger ones people will not be taking them. Mobility is not exactly a great feat, but it opens a few nice doors.

So those are a few of my thoughts - I do really like your idea though.