Now I took much thought in this with modern systems. Most of the Final Fantasies would need to use a lot of power to have the modern graphics.

Now if a Final Fantasy game was Remade with dumbed down graphics they might be able to create the vast world. I am stuck between Final Fantasy IX,VII and XII (being the easiest).
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Final Fantasy IX has a vast artistic world and could work if they made the graphics sort of cartoonish like Dragon Quest. It's probably the one I would like to see the most only because it came out when I became an avid Final Fantasy fan.
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The most successful of the 3 would be VII, because well its the most popular. Would it be good I don't know. I elaborate more in a video I made here: https://youtu.be/H9Bey5j6iH8
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FFXII was probably my favorite RPG for PS2, and has the easiest type format to make a remake on the PS4. With better graphics and maybe some extras like more back story and new hunts, this game would be awesome.
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What Final Fantasy game would you like to see Remade?