sooo it's pretty obvious Paige will eventually bring in NXT girls as back up. but does she bring Charlotte alone, or the whole 4 horsewomen thing?

I've heard the group theory, but I don't think it's happening. Sasha needs to stay down to be the top heel down there because... well... who else do they have?
It probably shouldn't be Bailey because she'd need a drastic character overhaul and also coming up would mean she would never win the NXT Women's Title.
It MIGHT be Charlotte, but I've heard that they'd keep her down there until the TapOut line comes out because she is one of the faces of it.
Becky Lynch seems like the most likely candidate.