Eh, if we're looking at competitive only, then Cloud would be on top.
He's got Komokiri maining him in Japan, M2K is putting in work in the US, and Serge and Leo in Mexico ended up deciding who was the best Smash player in Mexico via Cloud dittos after Serge's Lucario fucked up Leo's infamous Metaknight and Leo's Cloud equally curbed stomped Serge's Lucario.
I'm hesitant to say that Bayo will be top tier in the end. In a lot of ways (design-wise) she's what ZSS should have been. A huge amount of time obviously went into making her balanced. Strong, but fair.
The problem is there are characters in this game not as balanced as she is. As such, her poor frame data and potential might end up going the Shulk route than the Ryu route. While she has infinitely more options than her, I can't help but get post-launch Zelda flashbacks from Bayonetta with how a lot of her bread and butter special combos break down it seems about 30% before her kill moves become viable. I'm seeing some combos that like hype as hell and blow that concern out of the water, but we're going to need tournament evidence of those combos in action as opposed to against a training mode Sheik CPU.
Corrin is weird. Is he like pre-patched Diddy Kong where he can be picked up and win the tournament like no ones business, or is he like post-launch's Ike or Smash 4's post-launch's Little Mac, where we just haven't learned her yet? All I can really say about Corrin is that I'm just really, really, excited to see what Ken ends up doing with the character at EVO.
It TC is only interested in the character's competitive viability, you can't go wrong with any of them from what we've seen so far.