Yeah, any radical change such as setting the battles that manual would ruin the game for some long-time fans.
However, that doesn't mean the system can't be changed. I've never hidden my dislike for the d20 recently. Sure, it was great and it's importance is undeniable. But it's aging, and quite fast when paired up with some most recent systems.
I believe that such a change can be made and still leave the game quite automatic to please the ones who would rather not turn the gameplay into an action game. Anyone ever saw FFXII battle system?