For anyone who hasn't yet checked out the Nexus since the game's release, an inventory UI replacement mod has already been out for some days. It gives you a way more compact and useful inventory interface with clickable columns that you can sort by, and most importantly the value per mass column. The most important item stat in Bethesda games.

Another thing you can do is add temporary columns of many different stats to compare your items. It also shows that quantity of an item you already have while shoping. And probably other things.