I thought this was requested before but after searching for it I couldn't find results.
One thing that really irks me is how we have permanent quest items in our inventory. There's nothing we can do except toss them but if we do, there's a very good chance we can't get it again later on when we will need it in future expansions. The fact that we do have these items that can be thrown away is also very confusing to the player because what purpose do they serve now? Will they continue to serve a purpose? No one knows.
There was another thread requesting that Marni's stones should be separate and while I disagree with this idea, I do think that Quest items should be in its own category.
[ Inventory ] [ Pearls ] [ Family ] [ Quest ]
The biggest problem with quest items though is when you complete a quest (if it can complete that is) in a party, the item doesn't disappear. In the end, you do have a mountain of quest items that you have no idea if they are important or not lol! But that's a different thing altogether but my main request still stands, I think that a Quest tab would be well received.
Its the extreem lack of information that this game has; in the game and out of it, if it wasnt for bdocodex many of us would be lost. As when you do the main quest line(s) we get many items that we do not know what to do with them afterwards. At the beginning i usewd to keep them all from every char, but at some time there were so many filling warehouses and inventory, that i started throwing them away at the same time not feeling very confortable about this, exactla because i dont know "will i ever need this in the future?" So my feel is PA or whoever does not care at all, and its a proof of desinterest towards the players.
The quest designer could very well state in the item description, if it can be sold, thrown away, or even simpler, after quest ending make them vanish.
It may also be, that by keeping us unknowing and unsure, its a way of making us buy more inventory space (for trash), one way or the other, for a new player very confusing i am sure.
So a new inventory just for quest items would be a great improvement, and of course more information about those items.