I feel like the game would be improved by having single-use (or several-use if the case arises) items disappear from your inventory after their usefulness is up. I hate having a cluttered inventory especially when it's filled with every "a_bandit's_key_00".
I'm rarely confident enough to just trash a key because ya know, just in case... So if the game could do the heavy lifting and tell me I'm done with an item by marking it as such, or removing it from my inventory, that would give me great peace of mind.
Great idea. There is no real reason for keys to remain. Obviously, you can just put them in a container, but I believe your suggestion would be that much more elegant and definitely an improvement.