I have played the NES version done by Neo Demiforce, on an emulator.

There's not a whole lot of difference compared to the remake, other than the obvious cosmetic upgrades, though they did somewhat streamline the stat-boosting system in the remakes. It's rather oblique and hard to pick up on, though. In addition, the auto-retargetting algorithm is always a welcome change, for me anyway. I really have never enjoyed seeing that "Ineffective" message. :/

Demiforce's version may have been overtly simplistic, but it's the only way to play the NES version in English that I know of. I did enjoy it, but it's also inherently frustrating, due to the side characters being, for the most part, a liability in battle. Minwu isn't bad, but he's quickly replaced by, shall I say, less useful characters.

Especially Gordon. I don't care what anyone says about Edward from Final Fantasy IV, Gordon is The Load personified.