The system in place will correct for the mathematical bias against new characters if the standing population of characters is understanding, welcoming and inclusive. The same is true of new players and current players. If a given chapter is experiencing stagnation it's because they're either not recruiting or not welcoming new players OOG and new characters IG; after all, if an established player has a poor experience their first time at a given chapter they will have reservations about going back that may well have nothing to do with character power levels. There is more to the game than character cards.