1. Doomguy - I only got into Doom recently, but I'd love to see how they'd translate the series' gameplay (which largely focuses on being mobile, since standing still means death) into Smash. Plus, it would stop people from trying to shut down character discussion by saying that a franchise is "too violent" or acting like it's impossible to tone down a series to make it work in Smash. (it reminds me too much of the dialogue around Bayonetta and Ridley before they were added, where people said that Bayonetta was too raunchy or Ridley was too big, and that it was impossible to tone those parts of them down... until the Smash team toned those parts of them down)
2. Cinderace - I'm guessing that the final character is going to be from a somewhat-recent Nintendo release, and Sword and Shield seems like the main one that fits the bill. I don't know much about Pokémon gen. 8, and I'm not sure if Cinderace would be an especially original/inspired pick (we already have two other fully-evolved fire-type starter Pokémon, it seems similar to Lucario in terms of proportions, and I'm not sure what unique mechanics it could bring if any), but out of the starters from that generation, it seems to be getting the most focus.
3. Banjo and Kazooie - I've wanted them in Smash since I played the original Smash Bros. back in 1999, so seeing them in the game was a dream come true for me.