SE, if you want to really hit your fans with that retro nostalgia feel, having FF games with old and new styles would be just the thing. Replaying FF1-3 in nes style as well as the newer styles would mean alot to a wide audience of people. Same goes for FF4-6 in snes or gba/psp modes. Who wouldn't want to switch styles on the go every now and then and dive into new or old dimensions of the same game, compare how the games evolved over time? IMO that's how FF1-6 should be done. It's not a hard thing to do and is not something many or any games have tried to do. Yes, it'll take up more space, require some rescaling and adding more game options, but that's just about it. It's a money bomb waiting to happen.
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