Nothing about the gameplay needs to be changed.
Maybe us fans wouldn't care, but that kind of things doesn't sell.
It's one thing to pay 10 dollars to play it on PSN, but no one's gonna pay 60 bucks unless it feels like a game made today.
Things like world maps and pre-rendered backgrounds obviously don't fly anymore, as does turn-based gameplay with lots of more action-oriented bells and whistles.
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SuperNiceDog - 1, pjbasis - 0