I have some solution for level cap. At level 6 there is 1st exp cap, your battle brother should find proper trainer in city/castle and pay for some instructions 1000 crowns. At 11 level is 2nd cap, and training costs 2000 crowns. After 11 level every next level has own price, and after 11 level you gain perks only half time (on 13, 15, 17, 19 level, etc) and next level is more expensve (+1000 crowns). What do you think?