Yeah, but Carl rising in the tier list was solely because of the clap loop. It was obvious that the clap loop (very much practically an infinite except for some characters) was not intended, which was why they took it out. Now if Rachel has some undiscovered bug/overlooked mechanic with her moves that can make her deadly, she'll definitely rise in tiers. However, her current weaknesses (and pretty much lack of strengths either) are very obvious. She has poor damage output, poor zoning, and practically no mix up at all. I expect her to get a little better with time, but I really don't see her rising above C or C- tier.
I have a feeling H.H is going to drop her in the end in favor of someone better (probably someone top tier like Bang or Litchi until the next version) within the next couple of months. In Slash, he dropped Dizzy in favor of Ky, and Dizzy wasn't nearly as bad as Rachel is looking right now. At least Dizzy could zone well and had some sort of mix up with decent damage options.