Well you don't have to pile all cards in the middle of course. I only use parts of the adventure cards deck and have the others waiting somewhere else. I will probably do the same with the spell deck once this becomes too large.
I place it at one side of the board.
But i agree with Harlan Draka, that we need something that can hold our adventure deck. Especially if they are in sleeves.
I also vote for these wishes..
* A new NPC character is welcome (maybe a toad king)
* More events, places, strangers (including Gong, and Altar) for the dungeon.
* More cards that makes some spaces a draw 2 space (if overlays are not possible)
* Event cards that increase the enemies on the board with a +1 or +2 strength or craft
* A card holder on the table, where you can stack your adventure cards, spells etc
* More 7+ strength&Craft enemies for the mainboard