Most popular are The Undertaker, Hulk Hogan, Ric Flair, Razar Ramon and Lex Luger. I got two separate brands with separate TV shows.
There are also wrestlers like Bret Hart, Scott Steiner and The Million Dollar Man who are between these top stars and capped stars. I don't think there is a limit to major stars that a company can have because only few specific workers are impacted by popularity cap. I am still able to create new major stars with other workers (e.g. Giant Gonzalez).