That report of Charlotte being held back due to her looks was just smark baiting.
Seriously, Charlotte is hot, fit, Rick Flair's daughter, has Triple H's backing, and can wrestle. Anyone who thinks that WWE is saying "she doesn't have the look" will believe anything they read. She was pushed initially as part of a "snobby, mean girl cluque" gimmick. You think she would be pushed like that if WWE DIDN'T think she looked good?
And Sasha is georgous and like Charlotte is pushed as being a mean hot girl. WWE is not sitting around thinking, "how can we push this plain jane?"
This whole WWE only wants hot blondes with 34D's is over exagerated. Yes looks matters, but Paige, AJ, Gail Kim, Serena Deeb, Jazz, Jacquelyn, Molly Holly, Kaitlyn, Awesome Kong, and a ton others all in one way or another broke that mold. Yes all of them are/were attractive (well, I guess some would argue against Jazz and Kong) but they all in one way or another broke the mold people associated with Trish Stratus, Torrie Wilson, Stacy Keibler, Candice Michelle, etc. And all of them at one time or another got a strong push and in almost all cases a title reign.
Yes, WWE has a habit of hiring the hottest models they can get and figuring they will teach them to wrestle. But they aren't as cookie cutter as people think and do go for more variety than anti-diva fans try to paint them as.
Sasha may or may not succeed in the main roster, hell she may not get to the main roster. But anyone who thinks WWE is saying, "she isn't tall blonde and has fake boobs... off with her head!" is over exagerating.
If anyone in NXT would be in danger of their looks holding them back it is Bayley. And don't get me wrong, she is a cute and I would happily date her if it wasn't for the fact she would never have me because she could do a hell of a lot better than me without even trying. But she is more "girl next door" than the majority of the roster. But even then they have put Divas on the roster than are conventionally less pretty than her, so I don't think she would nessecarily be overlooked because she doesn't look like Trish Stratus.