Game does (and has always, with the exception of when host could "stack" rooms) been Top level BB on alpha, 2nd and 3rd on Bravo and 4th on Alpha. CV is done vice versa (considered the way to balance). Blitz rooms tend to go at Even numbers, not even classes. Get 2 or 4 BBs and 2 or 4 CVs and you will not end up 2 bbs 1 cv vs 1 bb.
Mog and Oyo are the only real ships that can mess up those calculations at this point.