No, I don't want any kind of inventory encumbrance. This feature in RPG's always annoyed me, since it meant I'd have to make multiple trips to the same place to pick up loot. Did it add to the realism? Slightly. It more often added to a sense of tedium.
I get what you saying man, I feel you.
I agree with reaze, NPCs should be able to pick up loot we leave on the floor (Preferably scavengers, bandits, or thieves) when we are not around (Preferably not psychic though, only if they encounter them on their route).
Instead of making tedious trips, now we have to make big decisions on what is more important, hide the rest you can't carry with you nearby and hope some thieves don't stumble on your temporary stash.
Important
The more we carry, the slower we become (And consume a little fatigue, like very little to the point if you are fighting it will hinder you, but not much if just traveling) and become considerably slower when over encumbered (And if you are carrying a ridiculous amount freeze us like in oblivion.
Why? In OB I move freely like a butterfly and when I pick up a sword I suddenly become immobilized...we should be warned before this happens (With our kleptomania) with some sort of slow down.
Sudden immobilization is anti fun.