To clarify I don't want them to drop the Dr. In Dr. Mario or start calling Sheik Zelda. In this particular scenario I would also completely do away with echo stacking. They would simply be placed right after their corresponding original.
I also disagree with the notion that it would be too confusing this way. This isn't something new to fighting games, though it is less common in the one's you're probably thinking of.
There are instances of alternative versions of characters in some older 2d anime fighters that were selectable from the same slot but by pressing the select or start button rather than the normal confirm input. That said that's also not how I think it should be done for Smash.
We currently have several buttons all mapped to scrolling through colors. XY, L/R, and ZL/ZR. One pair stays on colors. Another goes to toggling proper alternative costumes and the last goes to alternates when applicable. Or like you said they should just make a menu for it like other fighters. Characters with an alternate would also have an additional icon hovering over their render to denote that an alternate is available.
Going back to the names. I am still in favor of just calling both Ganondorf and dropping the Zero Suit from the actual annoncer call. Just add the particulars in parentheses in the records. And if you really want to give them different names just call ToTk Dorf "Demon King Ganondorf". It's a mouthful but so is Zero Suit Samus.
Records aren't enough. People know the characters strictly by name and compare them to the Records based upon actually playing the character.
It's inconsistent and doesn't solve anything. This isn't the same as some EX Idea. Like, if it was choosing a character and on the CSS it said Samus(Zero Suit), that's fine. But they need to be consistent for both so others aren't confused.
Other fighting games are different and don't work how Smash does. Smash treats every character with even the tiniest difference as an entirely separate one(even if they could be merged sometimes. Giga Bowser went through this, Metal Mario and Giant DK went through, and also are still kept as mini-bosses too at times, etc.).
It doesn't actually work. And Echo Stacking still sounds better because it's actually a consistent thing with no confusion. You still know who you're selecting. I'm not selecting Samus. I'm selecting Zero Suit Samus(or even Samus(Zero Suit) for a decent alternate name). And it doesn't matter if it's a mouthful. What matters is that it's clearly not the same character as the other one, so they are hard given other names so there's never confusion at any point for anyone.
Besides, it wasn't till way later that EX Costumes even got their own records. It was just the same guy with a special change(like in early Marvel VS Capcom). Which was already confusing enough, but at least you know exactly you were still playing as Ryu with the same record. They also had clone characters with sometimes their own names, but the records were clearly different even then. They never attempted to stack those kind, as it was way too confusing. There's a reason people called alternates things like Orange Hulk instead of Hulk, or say, Hyper Venom. People did give a few nicknames at times(for less confusion), but they still gave alternate names anyway.
It's very pointless to stack characters who aren't even some kind of clone at this point. It enters a much higher confusion than is needed. This is a very casual game. People know Link because he's a tall adult. People know Toon Link due to the artstyle and being a child. People know Young Link due to being a more traditional design, but smaller. Etc. These names are a massive deal in Smash and are heavy designations that are kept for multiple games straight. It confuses veterans and makes people wonder why on earth you would use an inaccurate name for no legitimate benefit. You could still stack them(assuming Echo stacking is gone) but retain their identical name without a single bit of confusion. Or the slight parenthesis variant. You may also be forgetting how Sakurai has gone on record saying Records were already difficult to work with, which is why he refused to do "Costumes with differences of any kind". Do you really honestly think he would use a more confusing route(or frankly, anyone who pays attention to Smash's history) when it only creates more oddities that don't need to exist?
Frankly, no. It's a terrible idea. It doesn't work and doesn't legitimately improve the game. Stacking is cool. Completely removing unique names is not actually a useful tool. Never mind how much it hurts even costumes who now at least kept unique names and have to give them up. Yay, Alph is now named... Olimar for no given reason. While it is true the records aren't as kind to Alph(something that should be easy to change, which is to make the most popular costume be noted in some way by changing the name only) or the Koopalings respectively, at least that's a case of Sakurai making it clear he has trouble separating data for costumes. In other words, it was never plausible due to clashing data that would be misleading. Now it'd be even more misleading, since it's not just a costume,
but a completely different character.
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As for TOTK Ganondorf or Pig Ganon? I frankly don't care if they're "based or related to a previous character". I think they're good additions because they're fun and unique. Pig Ganon alone took a while to even make a somewhat minor appearance. There's multiple Zelda characters that should get in too, and not even a reference to ALTTP Ganon, the most iconic form, is flabbergasting at this point. There's no reason he's not at least a Spirit by now. Him being playable would be a great addition. We have tons otherwise for notable characters(more than one version of Impa alone, two separate Tingle versions(Toon and regular. Toon is a lot more greedy even in his nicer games like MC, but also is a different person from the MM one, which never reappeared outside of HW respectively), and then you got the one-offs like Midna(with Wolf Link), Ghirahim, Demise, Zant, Beedle, and so on.
There's just a ton of memorable characters. Not getting a new one after Brawl is frustrating, agreed. But I frankly am not picky because there's too many with cool potential. (Note that I didn't even mention Toon Zelda and Tetra yet, and even funnier is that Toon Sheik was considered an ideal semi-clone akin to Toon Link first. Albeit, I feel like Tetra would've been done due to it being much more difficult to make an all new model at that point. Doesn't really change what the clear plan was. I do feel he considered Tetra at least, considering her being on a Smash Poll, but that's just a guess).
