For both after dungeon rewards and also storage.
For after dungeon 2 more buttons... 1 says discard all and when clicked it just discards all chests obtained in dungeon without asking if ur sure or not. And other button to keep all also without verification. Those buttons would be a little more distanced from the original ones... could be in the right upper side of the screen or right down side for ppl not to mistakenly click them.
For storage a function that would be something like multi select and then u could choose from 1 item to max a full storage page to either discard or open in 1 go.
Idk but i think those would be good adittions.