I'm not even that worried about his chances, just annoyed that we can't put this to rest, probably until release.
The more I think about it, the more I am sure he will be revealed before release. Some pointed out the tease around Palutena ; but it's worse for Ridley. We saw him moving, implying his model is done, being either a character or a boss.
And showing him, even as a shadow, is really important ; he is either the third boss ever revealex, or one of the new characters. We saw that G&W being confirmed at the round table didn't allow him to get his page on the website. It could be the same for Ridley...
Even if everything leads to his appearance as a boss. At this point, K Rool has more chances than him (his underlings being shown).
Two points that could actually make me think the contrary ;
-The trophy tease (one for Chrom, one for Impa, one for Palutena, one for Ridley)
-No pyrosphere explanations about the boss since the beginning.
Even if I'm the only one believinv the trophy tease, I believe !
Oh and I also believe the Sal Romano leak.
Leading us to 14 newcomers, add K Rool and Mewtwo (I count him as a newcomer) 16.
Add 39 veterans minus 4 (Snake, Lucasn Squi, Ivy) ; 35.
35 + 16 = 51. And it doesn't look impossible at all. Add one more if Snake manages to survive, 52.
Impossible ? I think not. And main Series (Pokemon, Metroid, Mario, Zelda) all get a newcomer !
But once again, I think he is disconfirmed.