Do you remember the last time you were slaughtering hordes of monsters and collecting phat lewt? Do you also remember going, man this is fun but i’d really rather spend a lot of time sorting and searching through my inventory instead? Yeah, me neither xD.
I suggest an advanced search option for stash that will allow you to filter just like you would in a loot rule. . In addition to that any items matching your filter would be displayed in seperate “fake” stash tabs. so if i search for say fire damage and elemental damage of t4+ all items matching that would be displayed in seperate windows where i could examine each one and take them out to place in my inventory if i wished.
If you were to place something in the “fake” tab have it automatically be placed in the first tab with enough space to accommodate it. BOOM. NO MORE SORTING. We spend less time doing what is effectively paperwork and more time having fun! 
I honestly think this is my best idea for any game ever. If anyone has any suggestions on how this could be done better please chime in!
-Val