As well as the few mentioned above, you could also just specify in the description that BLU or Limited Jobs are not accepted in your party. Anyone who joins as a one of those and doesn't want to switch, just kick them from the party.

I would however agree if the Play Style section in the PF criteria where it states "Beginners/First Timers Welcome" also has another tickbox for "No Limited Jobs", or something along the lines of that.