Anyway, the point being divine power source is a mess. There are now 6 clerics, 4 paladins, avengers (yet another divine warrior!), the invoker in its various configurations, and the poor runepriest crying in his corner.
Well, to be fair... the runepriest isn't really a divine class. It only got shoehorned in because the more logical power source (arcane) already had an abundance of classes in it.
Claiming that the gods power runes is a tenuous justification at best. For that reason you could make any class a divine class. Heck, warlocks are closer to a divine class than runepriests are, because at least they are granted their powers from a planar source.