I do not understand all the hype with Chorus Men.
The Chorus Men/Kids are a unique kind of character that would function very differently and have a few qualities similar to G&W and the Ice Climbers, 2 of the best designed smash characters ever. I don't see how that's a bad thing. There's also the rhythm elements, which sound pretty cool if done right. I've heard ideas for a character with a rhythm mechanic thrown around for a long while (specifically with the Elite Beat Agents back pre-Brawl).
The Chorus Men/Kids also don't really come off as a kind of niche that competes with a character like the 3 top dogs in terms of support as potential newcomers (Dixie, K. Rool, and Ridley [and Rayman not too far behind]), so it's not like the Chorus Men/Kids serve as a threat to getting in over them.
Heck, Dixie and K. Rool aren't even "real threats" to one another, because they also fit under different niches.
There truly is no real substitute for Ridley and K. Rool from a gameplay, aesthetic, or character design standpoint.
I don't know why we would need to feel "threatened" by these characters. I mean, there was no substitute for Mega Man, the Villager, Miis, Robin, Shulk, or Little Mac, and look how that turned out.