Imo they should make leaders restricted until you reach a certain level and then you can use them. For example, you can trade/sell/hold Ambre but you must be level 35 inorder to use her. This is to prevent low levels from cheesing their way into winning. Also, this might help new players learn how to play the game insted of overpowering their opponents with cheese cards. Furthermore, this restriction might add a little rarity to leaders because you must be a certain level to use them which means actually playing this game for a while to be able to use the leaders( granted getting to level 50 isn't that difficult with the guild bonuses and dm). That's my 10 cents worth.