I organized a friendship league with 6 players from Diamond and Ultimate leagues (140%-160%, they usually cost 100-200€ per season), and 8 players from Gold and Platinum associations (90%-110 %, they are free but very experienced players).

The current ranking is directly proportional to the money they spend. I've also watched their guild games, and the free players usually don't have any advantage. Unless he joins a strong guild (the other 5 players are spending money and he is responsible for lowering rating stars)