I'm going to assume you were referring to this post:
I think the biggest thing is that we know that she was considered to be in Brawl. That to me makes it seem like she might get considered again due to the fact that a big game involving her (Spirit Tracks) has since released. She could also be used to market the Wind Waker HD. If the Wii U version gets a Wind Waker stage, Toon Zelda could be there to represent a Zelda stage on both versions.
As stated earlier, this is the only evidence I agree is "significant", but I question how significant it really is. I don't remember Spirit Tracks being all that big of game, and it doesn't help that it was released all the way back in 2009, and thus instead we've been getting tons of Skyward Sword content. As for marketing potential for Wind Waker HD, I don't believe Toon Zelda has marketing potential at all; why use her to market a game that has not only long been released, but that Toon Link himself markets just fine? Even further, why use Toon Zelda to "rep" the Wind Waker stages if Toon Link can already do that just fine?
I posted a thought I had in the Toon Zelda thread a few days ago after I saw the Phantom Trophy in the Pic of the Day. I think that it's very possible that the Phantom model used in the Trophy could be the model that Toon Zelda would use for her version of the Phantom Slash move. My reasoning being that it resembles the Phantom that Toon Zelda would use in Spirit Tracks, and they could have just used the model that Zelda's Phantom Slash uses, but they created another model for the trophy instead.
But couldn't this also be interpreted as somewhat worrisome for Toon Zelda? Especially after Spirit Tracks, if they wanted to add Toon Zelda as a character with some deviations, having her playstyle based off of her Phantom Assists was the obvious method of doing so. Yet instead they threw the phantom on Zelda herself, despite that incarnation of Zelda having little connection to summoning Phantoms.
I can understand the logic that possibly Zelda using Phantoms at all could be a nod to the Phantom Zelda games (and, in turn, pertain to maybe Toon Zelda) but relegating such an obvious method of attacking for Zelda (and using the similar design for possessed Phantoms) to instead of Toon Zelda doesn't make me hopeful.
Speaking of Zelda, have you noticed that many have been complaining about nerfs and changes that they gave her in Smash 4? You know that people also complained about Marth feeling nerfed in certain areas as well? Guess what we got a few weeks later. That's right. A Marth clone in the form of Lucina. I feel as if they changed up Zelda in too many areas that wasn't necessary. My theory is that she might be receiving a better air game, while Toon Zelda receives a better ground game, assuming she's on the roster.
Zelda wasn't meant to be "nerfed", and there were even PoTD's highlighting her buffs. It's obvious that the developers wanted to have Zelda stand out as her own character in this game, especially since Sheik always overshadowed her. Thus, after all that it seems counter intuitve to intentionally nerf a character that desperately needed buffs in many areas just so that Toon Zelda could acquire slightly different attributes of her.
Lastly, there are so many reasons people say that certain, more popular Zelda candidates won't get in. Ghirahim being in one Zelda game, Vaati not being relevant anymore, Ganon being just a Final Smash. I've seen almost no arguments that goes against Toon Zelda's potential inclusion, besides the regular three Zeldas being too many. Even that is just a conjecture. I have some more points, but I think you get the gist of it. The pieces of the puzzle are there, but nobody wants to put them together.
To be fair, the only possibly candidate here that has a stumbling block is Ganon, since he needs to graduate from a Final Smash to be a fighter (presumably), but Ghirahim and Vaati, even though I find them unlikely, I don't believe that have all that much more against them then Toon Zelda. And that's only because she was planned for Brawl, which gives her a slight edge.
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