I'd say Gau, because you can raise his stats, plus, not counting Gogo also using the same Rage, he's the only character able to use Flare Star by having the Io Rage (number one reason as to why I love him so much).

Also, Gogo can use magic. The magics available to him depend on the magic available to the characters of his team. Not sure if it depends on the turn (example, Setzer not having Ultima, then it's Gogo's turn and so he doesn't have Ultima too, as he would have the exact same spells as Setzer; but if Terra had Ultima and then it was Gogo's turn, then he would have the same spells as her, Ultima included), I don't think so (meaning I believe it eitheir has the spells from the one that has the most of them or a joint of the team's spells [all party members spells combined]). But Gogo can use magic, and that's also where he is stronger in between physical and magical strength (no surprise that his Desperation Attack is Punishment Meteor, which in itself is a reference to FFV's Gogo who often uses Meteor if you actually try to defeat it).

I will be teaching Gau Ultima and Curaga with Cyan, Shadow, and Mog. (And since five party members know both already, I'll have Edgar be the Cactaur slayer when teaching Celes, Strago, and Relm)

And maybe I might put Gau with the Goddess party and Mog with the Fiend party, Goddess goes down fast if you have Ultima while Mog can use a Dance to make the Fiend battle easier. Of course he won't be using Northern Cross so it'll be easier than the Pixel Remaster. (But for good measure I taught every character Fire. Well, except Gau, coz I thought I would replace him with Gogo)

Well, the game is yours, you take whoever you want and do whatever you want. No matter what, I always make sure everyone learns all spells. Like that, I can use whatever spell with anyone, including Gogo, as by having everyone with all spells then so do they for sure. The Veldt is definitely the best place to go to learn spells without levelling up and leave the levelling and stats raise for after that. The perks of the enemies not giving EXP in the Veldt is that.

Refresh my memory, what is the recommended level for Kefka's Tower? (I don't know if I feel like getting them higher than 50 atm, should I get them to Level 55 or 60 or something? Shadow, Relm, Strago, and Celes are Level 50 and up, will level up Locke, Cyan, Mog, and Gau next, and then of course, Terra, Edgar, Sabin, and Setzer. They all know Curaga and Ultima by now. Then go dragon hunting, Cultists' Tower, Dreamscape, then Kefka's Tower)

Hopefully I can kill a few brachiosaurs and get at least three of that item that reduces the cost of all MP to 1 so I can have much easier Curagas and Ultimas in Kefka's Tower

For me, I always need my characters at least at level 60, but you do you. You still got stuff to do anyway, so you'll level up while doing that.

Well, Ancient Castle and Dreamscape are the main ones that will have random encounters (I'm bringing Mog into Cultists' Tower with Molulu's Charm as having to fight enemies with only magic would be annoying), and that'll mainly be Terra, Edgar, Sabin, and Setzer, and one of them will be absent for the Dreamscape as I need Cyan in the fourth slot, asleep.

But, they'll probably go up levels in Kefka's Tower. Or should I level them up to 60?

They're all Level 60 (cept Gogo and Umaro). I get Gau with a Thunder Shield for Thunder Dragon as I am putting him with the party that will fight Gold Dragon, while Relm has a Flame Shield for Demon, and characters with weaker shields in the Fiend party have Ice Shields. I gave Setzer the Gladius and he actually hits harder than Terra now. I gave the Zantetsuken to Celes, and the possible Stop-afflicting sword to Shadow. Considered giving the Man-Eater to Relm but not sure if a non-brush weapon will prevent her from using Sketch.

I killed the six dragons outside of Kefka's Tower and Magic Master. After the Dreamscape, will head to Kefka's Tower and see how this turns out.

Sadly I only got one Celestriad. I gave it to Terra so she can do near unlimited healing.

Oh, Gogo is winning now?

Dude, this is a poll, the results will be constantly changing. One moment you look, Gau is winning, the other Gogo is winning and in the other they're tied. What's the surprise in that? Certainly you expected that to happen, yes?

I expected it to be more one-sided I guess.

But I do remember against Fiend last time, everyone except Gogo, the one who couldn't cast Fire, being frozen. Except in original Steam version he dies before he can use Northern Cross. That freeze debuff should not be a part of the game. Can't it at least have something to block it?

Anyway, I beat the game, none of the bosses really gave me any trouble, and took Gau with me where his Stray Cat Rage was useful against enemies and Gold Dragon, and he cast Ultima against Ultima Buster and Goddess. I forgot to have Relm sketch Kefka, instead casting Ultima, but it didn't matter, he died before he could even say "The end draws near".

And, I think I would put FFVI slightly above FFXII like I originally thought.

That concludes all the FF games I had planned for this year then. Well, unless I decide to do a second FFV playthrough where I try to get Forza and Enkidu to appear before I beat Magissa and Gilgamesh too fast, but that will be for later, I'll need to recharge a bit after all those Cactaur and dinosaur fights.