Not sure if there's such a mod, LOL. So currently i have a mod that allows me to carry as many items as i want (encumbrance goes into the hundred thousands i think) and i've been looting the hell out of everything being a thief. Unfortunately after a certain number of items i start lagging whenever i interact with my inventory, so looting a chest would take about 2-3 seconds of inventory load time which is annoying. Would there happen to be a way around this?

If not, is there a mod that stacks similar stolen items together? Cause right now if i steal 5 silver forks, they'll appear seperately as 5 silver forks in the barter screen. And clicking 5 times + loadtime is really frustrating.

Once you have a certain number of items, the Inventory Screens slow down. The game was not designed for unlimited inventory and it will even lock up or CTD if you have too much in there.

There is a Key Chain mod that helps by hiding the keys, but it won't help you much if you have 100 forks in your inventory. The reason they are listed separately is the ownership is tied to the reference id, not the formid. The referenceid is generated when the cell renders (or maybe when it is created in the editor and the item is added, not sure, but it does not matter for this discussion)

Which begs the question, why are you stealing forks?

If you really want to loot to your hearts content, pardon the pun, then go back to your house/merchant/fence in between dungeons and drop stuff off.

You might try using the http://www.nexusmods.com/oblivion/mods/4065/? to hide some of the things you have until you can sell them. This would split your inventory up into usable stuff and stuff you will sell later. If you keep that much in your inventory it will always lag. I know how it is because I'm a packrat too. You will just have to take the time to go to merchants more often to get rid of the junk.