Drop one class/add one class

Which established FF class would you put in the original Final Fantasy that isn't already there? In order to do this, you have to get rid of an existing class.

I would get rid of the Monk/Grand Master and replace it with a Dragoon. What about a class promotion, you say? I suppose it would be something like Dragon Master. Jump time would be decreased OR you can attack multiple (but random) enemies!

I'd swap thief with gunner.

I'd take out the Red Mage, he just didn't cut it end game. Id replace him with a animal trainer class of sorts, where he must capture creatures and unleash them in battle at other fiends.