Here I do disagree. I won't argue about who the main villain is just because that's an argument I'd rather not get into. But...
1. In video games there are main villains...and then there are final bosses. Even in games where the final boss clearly isn't the main villain the final boss is still a big deal, and some times people focus on the final boss or even an after game boss more than the actual villain.
2. Main villain or not, plot significant or not, just going off of my personal experience of people I talked to, Ganondorf upstaged the living hell out of Zant. As opposed to say Skyward sword where it was Giraham who upstaged the hell out of Demise.
3. In fact, about half the people I've talked to who played Twillight Princess said they thought the final battle with Ganondorf was the most memorable thing about the game(the other half say it was Midna with of course a few other opinions here and there). People were wanting a swordfight between Ganon and Link for as long as Ganondorf's been around, and for whatever reason a lot of people weren't satisfied with Windwaker's final duel.
4. Ganon was basically just being Ganon in Twilight Princess. He often(though not always) just sits behind the scenes and influences things indirectly up until the very end.
And regardless, he added nothing of interest to the game and was pointless overall beyond a fun boss fight. None of those convince me was a good idea to add to the plot itself. It'd be better if he had nothing to do with Zant at all, and randomly grabbed Zelda when her power was gone. Making him related to Zant cheapened him to a lame background guy. He didn't even have any real significance at all to the plot beyond "Zant got his power from him."
Also, does it matter what is most memorable? He was still not worthwhile overall as an important character in TP. Zant was. I hated Ganondorf's appearance in it from the start, and any role he had in the plot was fully stupid in my opinion. That's my final answer. If the Triforce had any real significance and physically existed(not just the power, but was the main part of the plot), I think he might've been interesting as an addition. But without it(being key to the plot), I see no reason for Ganon or Ganndorf to exist in the game. Note, that's also the stance of Aonuma. I just agree with it.
Again, I'm talking about things that influence fan opinions. Not things that influence design decisions or that are canon.
And Sakurai likely doesn't care about solely about fan opinions. We're talking about what could happen. I'm being realistic and know it wasn't going to be used in Melee, and for good reasons. I'm glad he got in in the first place.
I wouldn't be too sure, I think stance changing sidesteps a lot of the possible problems involved in transformations characters. My theory is that the transformations are gone because of technical issues, which would be greatly lightened with a stance change that doesn't change the character model. You said in an earlier post you thought they were gone because Namco-Bandai were pushing for balance, and NB LOVE stance characters and balancing a stance character in a game where no one else has multiple stances has been done(Gen from Streetfighter for example, and yes I'm aware that's not a NB game), I don't think they'd be against it. Also stance characters flow much better than transformations and you can do more things with them.
It's not whether NB likes it or not, it's whether Sakurai considers it equivalent to transformations. They are the same thing overall, just done differently, namely the action it takes to go into that new form/mode. Otherwise, identical in practice. Sheik is pretty much a different playstyle for Zelda(before 4), no different from a stance.
We don't know if he wanted transformations gone because he wants one main moveset per person. That's a very possible thing. I wouldn't put it past him either. It could be technical issues too, as Brawl showed.
Here I disagree again. For starters, Ganon's been long established as a weapon user (since Alttp) and the sword gave his Ganondorf form a weapon that suited him just as the trident suits his beast form(and I do think it suits his design and personality very well). Second, Ganondorf is one of those types of villains who's supposed to be intimidatingly good at everything, in that sense the more skills he shows(including swordsmanship) the better. Third, even if we ignore developments of the later released SS, in OoT Ganondorf get's his entire glorious kind of the world life ruined...by a swordsman. And the sword of evil's bane. He doesn't show it directly much in TP, but he's gotta be vengeful about that. From a midevil perspective it's not unreasonable for him to take on the primary skill of his greatest enemy nor is it unreasonable to want to best his reincarnation in a duel of swords. It let him have a real showdown with bane of his existence that's much more personal than defeating him with magic. Also just from a writing standpoint it's often good to have at least some commonalties between archememys. Well now Link and Gannondorf are both master swordsmen.
Ganon and Ganondorf are always separate entities in how they fight. Ganondorf is a human who was a pure magic user, but also could ride a horse. It wasn't till WW he could wield a weapon(he was likely trained in twin swords style in OOT due to being a Gerudo, but that was it). In TP, he used the sword he pulled out of him instead(I haven't played that fight in ages, so correct me if I'm wrong. No, Zelda Wiki didn't mention it, so...). To be clear, it's only likely he used the sword because it was there, he had no other. It was just convenient for him at that point. That said, Ganondorf existing doesn't mean he will use a weapon automatically. OOT proves that's not always in the plans. In fact, we see a knife sheath on him, his more likely weapon, but hey, thieves.
More importantly though it added a lot from a gameplay perspective. It's far from my favorite boss fight in Zelda and not quite my favorite final boss(I prefer fighting Ganon in WW), I think the four part conclusion of TP is the best designed boss fight in Zelda. First part-obligatory battle against magic with a pingpong of doom element. Second part-Fight against huge monster with puzzle elements and archery(they even snuck a use of the wolf form there). Third part-horseback riding and Link/Zelda tagteam. Four-Swordfighting (and fishing!). There you go, that's basically Zelda with in a nutshell, all that's missing is a fight use ever damn one of your items. Without the sword part it just wouldn't be complete.
...and people just like swordndorf a lot. And swordfights in general.
I'll take OOT over it any day. Anyway, the one thing to note about Ganondorf is he always starts off with some kind of magical move and the final fight has swords in it. The problem is? It's not Ganondorf always wielding the sword. This is why I can't really say the sword is integral to him like the Trident is often integral to Ganon(Only in the first game does he fight without one, but the NES likely couldn't handle the trident itself when the made it, or they never thought of it yet. His fight is somewhat similar to ALttP, where he shoots tons of fireballs at you while teleport spamming. They're still quite different, but a similar concept is there). For the most part, I've noticed his 2D Ganon fights tend to be ALttP clones to a degree. In 3D, Ganondorf always does something with magic, but not always a sword. And there's the kicker; The sword is not integral to him,
magic is. First, let's note Ganondorf never officially wielded a sword in any game till WW, a game after Melee. It's obvious why he didn't get a sword, he never actually had one. The tech demo means little at this point. That was never a game overall. It was just a fun idea. It used the OOT Ganondorf model, so Sakurai threw it in as a bonus, to the point it was fully in the game and could be on his model. As in, the programming is there. Now, I would normally say "maybe he considered having the sword in", and that makes sense, but he made it clear in the Japanese website he ultimately found him fine as a clone overall and went with that. If not literally the main reason he was in(popularity was another).
Here's the problem with the Hijacked by Ganon situation; It only goes off well if Ganondorf
acts like a mastermind. He was a mindless monster in TP, having enough mind to take control of Zelda's body. He had enough thought, but he never really did anything but act out of a blind rage at best. It was a pointless addition to me. If he really honestly acted way more like his OOT or WW self, I'd like him more. But he bored me to tears in TP. Again, the fight itself was fun, but his role in the story, to be frank, sucked.
An extremely heavy sword user that also uses magic and has several odd property projectiles like swordndorf could be would be pretty unique for smash, while still feeling like an opposite to Link(though it would end up a bit similar to Isaac I suppose...).
Or we could hand that over to a character like Isaac, who, while not strictly heavyweight, does everything else. I think he does the job way better and Ganondorf does the job perfectly of being the heavyweight magic user, something we don't have beyond him. More magic, and we're good.