The NES version of FFIII is significantly more polished than both of its predecessors. It's like they flipped a switch to instantly fix every problem those versions had. The problem is the fucking balancing. You have to grind after nearly every major story beat and it's so tiring. Definitely play the DS or Pixel Remaster versions if you want to experience III for this reason alone.
The job system in general is a bit disappointing. Advertises itself as having so much freedom and then a decent amount of the game practically forces you into an all mage party, or forces you to have dragoons, etc etc etc. It's not egregious, but FFV proved how far you can really take a job system. The gameplay in III does have its moments though, and it was obviously extremely important, starting so many iconic jobs and abilities from FF as a whole. I love the world and the general vibes, and the music wraps everything up in an enjoyable little package.