See the thing with other Fighting games and their Last characters is that typically, Most, if not all the characters Games like Street Fighter, Tekken, Dragon Ball FighterZ, Soul Calibur etc, ALL Appeal to the Same Hardcore audience invested in the game
When they do have a Guest Character, they will typically reveal them first. Negan is a perfect example in Tekken 7 since he was actually the Last Character released, despite being among the first revealed in season 2
The DLC Fighters tend to be Veteran Fighters that already have shown appeal to the Audience. The Last Fighters revealed have typically been Brand New, never before seen characters. SFV, Tekken 7 have all went this route, but they also might be another Veteran, like with Soul Calibur. I think Samurai Showdown actually have it's Latest character be a Guest character (Baiken), though I'm not sure if the game is done with Support
DB FighterZ is a Game that's strictly about Dragon Ball, and the First batch of DLC Characters, to the Last DLC Characters were all Dragon Ball Characters. the last character in FighterZ was SSJ4 Gogeta, and while he did get some flak from people from being Another Gogeta, People did want SSJ4 in the game
Mortal Kombat 11 is weird since they have their characters revealed in Packs rather than Separately, and all the Last packs of Both the Recent Mortal Kombat games and Injustice 2 had some sort of Guest Fighter Present. MK11 ended with Rain, Mileena, and Rambo. Rambo might have not been Spawn, but he was still exciting enough, and People were all over Rain and Mileena
Smash is different from all these games, taking the most similarity to Mortal Kombat in it's frequency of Guest Fighters, but since all the Veteran characters are already in the Base Roster, and Smash is not gonna make a Brand New Character to add as DLC, it's relying solely on New Characters, which is something that none of the other fighting games do.
Nintendo seems to Priotize appealing to the Most audiences it can, and you see this with the Variety of where the DLC Characters come from. You got appeal to RPG Fans, Fighting game fans, Platformer Fans, Playstation Fans, Minecraft fans, etc.
The Main reason I bring all of this up is that when it comes to the Last Fighter, I'm thinking if it's not gonna appeal to a New Audience, it's gonna appeal to the Audience that is already invested in the game, and that's a good thing one way or the other.
That's why I have faith in whoever CP11 is to be a very enticing and exciting character. I don't think they'll do a Promotion character since all the Games are either too early or Too Late. Byleth was added when People were already invested in Three Houses, and same thing with Corrin for Japanese audiences, and Bayonetta was there for the Left out European and U.S Fans, as those are the reigons Bayonetta seemed to do really good on the ballot
I'm guessing the Main thing people are worrying about is a Pokemon. I guess it's possible, but I have faith CP11 is absolutely not a Pokemon.
I think when you count those out, all the viable options for characters to be CP11 all seem to be choices I think a Good amount of people will at least find interesting.