Honestly after Byleth's reveal, I don't even know what to expect for newcomers anymore. Byleth was the ONE pick I was 100% confident in. Right now? No other character really seems to stand out to me.
This is something that I really agree with. It feels like there's no 100% sure option right now. Even characters who have a lot going for them have at least some blockade in their way.
-Crash has to deal with a language barrier and an owner that could be potentially difficult to work with.
-Same deal with Sora.
-Heihachi, Lloyd, and KOS-MOS have to compete with each other (assuming we only get one character per company). Likewise, Heihachi may also be competing with other FG characters if there's only one in the pass.
-Same deal with the Capcom Class (Dante, Amaterasu, Phoenix Wright), the Microsoft Militia (Master Chief, Steve), and the Square Squad (Geno, 2B, and possibly Sora).
-Doom Marine doesn't seem to have an NDA up, so he's out.
-Gen 8 Pokemon have that spirit event, which may or may not deconfirm them.
-Ring Fit Trainer is from a very new series, when Sakurai has traditionally been unwilling to add "unproven" IPs to Smash.
-Ayumi may still be Japan-locked, if the Famicom Detective Club remake doesn't get localized.
-Legacy Nintendo characters are potentially spirit-locked and have to deal with a precedent that has yet to include them.
Now, that's not to say any of this is a deal braker (with the exception of Doom Marine, that seems to be a pretty hard blow.), but it makes it difficult to put all my money on any one character.