The only issue that I foresee with this approach is that there is nothing stopping a silver ranked player from utilizing these cards in the bronze league making it even harder for those close to breaking into Silver from doing so. I come across many opponents when I am finally breaking into Silver that have more than enough power to be in silver league but never agreed to enter into Silver. I can only assume it is to farm a large number of lower level rewards to level/rent. Though in the bigger picture that doesn't make sense, it still happens regularly in my experience where I fight people pushing silver 2 or 1 still fighting in Bronze. Quora sucks, but I've beat her without my gladiators, prior to Rebellion using strategy!