I am pretty new in this game, but i feel like having an Auction House is a must, if you can be selling your mons while you are doing other stuff it would be pretty satisfying, and not only be able to sell mons, if you can sell items, like potions, rc etc. Would be much more accesible for new players and confortable for the older ones, even if the auction house its on 1 or 2 cities in each region.
I have not read anything about that suggestion, i am sorry if this already have been denied