You know, I think I'd be ok with it if the epic feats for casters and noncasters were comparable, but as-is, it just exacerbates an already severe balance problem. I'll restrict the granting of epic feats to epic void disciples.
Nooo, just ban the casting feats! I love giving my melee Dire Charge, or the archer Distant Shot.
But seriously, just fluff it as the Void Disciple not being able to grant magical power or something.