In order to gain ranks quickly you must play opponents of the same rank as you are, same as it is in the arcade version. When defeating CPU opponents of the same rank as your character it usually only requires 3 to 5 wins to get a promotion.After your fight has ended in Arcade Mode you can select on of 3 opponents with the directional pad, you can't always select an opponent with the same rank but do so when one is available. You;ll have your character rank maxed out in no time.