It really doesn't take that long to sort your inventory, hell, if you only pick up stuff _worth_ selling, you don't have to do it that often anyway. There was no autosorting in D2 and it was not missed at all. I like having to open up inventory and think of clever ways to fit things in, it also makes it interesting in multiplyer when there are a few players racing to pick up an item. You can get pretty skilled at sorting ur inv to make the right amount of space.
Maybe I am the only one who thinks this though
Peace