One of the fundamental "issues" I have with non-fixed decks is that they highly favor veterans and high MMR players (as you seem to be randomly matched against people MMR wise). Sure, there is QD, but it's also fun to create decks for leagues. So, I'd like to see a non-fixed deck league with a more even playing field. I think making "Peasant" an official league is a good solution to this. Here are the rules, but basically, you can only use common and uncommon items.