OK that makes sense. I'm kinda sad that they didn't go through with that now because it would have made her more interesting. Terra and Celes' character arcs are pretty similar in that regard come to think of it.
Shit was much edgier in the original designs. I think Terra was going to die at the end and Locke was a Dark Knight so he got all his power from cutting himself.
Locke wasn't a Dark Knight. He was, however, kind of emo and had Runic as his special. Terra was originally going to be male and the intention was indeed for male!Terra to die, but they figured the story worked better with a female, and reflecting upon it, having a character deal with so much crap and not get a satisfying conclusion would be a dick move.
Also Male!Terra and Emo!Locke were apparently going to be shonen (Friendly) rivals, so that also suggests Male!Terra's personality was going to be way different as well. If Locke was similar to the Locke we got now, it'd be easy to picture male!Terra s a Cloud or Squall-style protagonist (...not saying those two are the same, because they really aren't, but they could be argued as falling under the same general umbrella if that makes sense. Basically, Cloud and Squall are more similar to one another than either are to someone like Zidane or Tidus.)
In fact, Male!Terra was originally drawn to look like Squall!
Linking to image since posting it seems to lead to it being too small.That was extremely early concept art done by Nomura for FF6 in those stages. Most of the characters should be identifiable for one reason or another (case in point, guy holding Dice is obviously Setzer, male with Bandana is Locke, etc.) For the ones that are harder to figure out:
Not!Squall in the middle: Male!Terra most likely. The placement, Nomura's statements about how he feels about certain character roles, and the fact that he's known to reuse designs suggests that's who this character is.
Female in the bottom right-hand corner: Angela, I think her name is; the whore of Nikeah. I believe she was intended to be playable, and be modeled after the FF5 Beastmaster, whips and everything, as well as suppose to be Cyan's foil of sorts. Sort of process of elimination given the only other Young Adult Female on there is probably Celes given the sword.
Old Woman: Strago's Wife, a Geomancer. A dropped character whose purpose sounds like it would have been to get into Old Married Couple arguments for comic relief.
I think there's a handful of other Early Nomura concept designs for FF6, but this is the most interesting because it shows the original intended cast. The others are things like "look at the Figaro Bros., Locke, and Cyan together!" or something along those lines. Also ones from FF5, but those seem to have been done later in development considering they all more or less look like their in-game selves, save for Bartz's spikey hair.