Being able to save more items would be really interesting. Now, we either get all materials in a single game or we have to restart it all over again. When playing multi player, disconnects are absurdly frustrating after u`ve been hunting for a few hours to make a recipe and single player is quite boring, imo.
Not only for materials, to be able to save diff items, and make it easier to change strategies. For example, keep using an Orc Slayer, while you upgrade a Maul and keep it on the stash.
I know the code would be too long, so it could be done separately and be optional, somewhat like banks in TBR.