1: BTmod - One of the first and still the best. The author states in his description that this mod "improve many aspects of the stock Oblivion UI". Understatement! This is the essential mod you need to fix up stock Oblivion's poor menu system and interface. Also check the screenshots of the mod in action: updated journal, larger inventory screen, cleaned up main interface.

2: Natural Environments - Users of the mod all agree: this mod is worth a 10 ;) Using textures and some ESP file tweaks, and at only 9.3 MB, this file will give your Oblivion experience an enormous overhaul. All you can do is gaze at the quality of this mod: screenshot 1, 2.

3: Elven Cartographers - Map & Icons - Bored with the Oblivion map? This is an extensive retexture mod, fixing map and map icons. It's also compatible with the excellent BTmod - no reason to not use both of these mods! Before and after the mod is applied: what a difference :D

4: Dragon Knight Armor & Talon of the Silver Hawk Longsword - From the mod's description: "New items based on improved Imperial Dragon Armor, reskinned mainly to go from the annoying pink to a nice steel gray color". Check out the Talon of the Silver Hawk longsword and Dragon Knight Armor screenshots and download the mod right now ;)

5: Saddle Bags - Lore-friendly, Daggerfall approved. This mod adds saddle bags to horses, allowing you to transfer all your heavy weaponry and inventory items onto your horse. It's even compatible with the official Horse Armor mod - there's no reason not to download this!