I like the idea, and a lot of the execution. And I'm rather amused that upgraded Fighters and Paladins are only fit to be NPC classes. However... apart from convention, I see no point in having them be more than, oh, 5 levels long. More than that, and I feel like an individual starts being important enough to have levels in a "real" class, you know? So I guess the question is, "do you think there would be enough high-level NPCs with NPC-class levels to make things like the Adept's spirit quest ability significant?"

...and I have to agree that the Holy Warrior and Huntsman are too much. Not necessarily from a power point-of-view, but they're too complex to make good NPC classes. Too many choices, too many moving parts, and they definitely don't need casting as good as the Adept's. For the former, I might cut it down to Smite, Lay on Hands, and Turn/Rebuke Undead. Maybe the mount, too. The latter can have his skill points, tracking abilities, and Favored Enemy. That should be more than enough.

Where's the Expert?