Also shenanigans. Those are two of my favorite words. Now... where was I.... RIGHT!

Some ideas I had that I've always liked as mods in Morrowind and Oblivion:

Primary Needs (Eat, sleep, drink). Would make life in the game much more interesting. Since travel will be a big part, I assume, it would make it more challenging and more interesting.

Companions. Pretty self explanatory. No quests involved, you can just pick em up pretty much. I'm thinking 3 kinds... Hirelings (Pay them and once you dismiss them you have to find them where you did originally and pay them again), Buddies (Do a little dialogue with them, maybe do a quest for them or something and they'll follow you around. Once you dismiss them they go back to wherever they'd normally hang out but you can pick them up any time.), Animals (Dogs, bears, anything you could have as an animal companion, you could buy one, find one, tame one, etc and possibly train it. When you dismiss it it goes to your house.)

Houses, obviously the player should be able to own a house, but I'm thinking maybe the player starts the game with a lowely hovel wherever they start, just because I hate having to save up for one and having no where to stash my loot. (or maybe the character at least has a placeable tent)

Families, the player can have a wife and kids. That's all my thinking on this.

Make Marksman worthwhile. Personal beef here, but in Oblivion, being an archer SUCKS.

Fatigue. If your fatigue drops to the bottom, you fall over or faint or something. Make walking and horse travel more appealing.

That is all. Just some ideas I had to improve the game.