If they don't spend time making a new engine for every new numbered FF release, I think they can achieve that without too big an impact. They are currently using the Crystal Tools engine and that new fancy engine (I forget the name) and have also noted their intent to use the Unreal engine again very recently. So... who knows where that will end up.

Maybe if they rush out the games then at least a couple of them will be received a bit better, although to be honest I think the fans often have too high (and too specific, perhaps) an expectation when it comes to Final Fantasy games. They're still better than any other "high-end" JRPGs out there, to my knowledge.