Ye hast taunted me out of my lurking while I am caring for a newborn, and going back at school. Curses, why must I be compelled to shit post in Oblivion mods threads.
Short answer, No.
The main flaws of oblivion still exist in most of the mods. shitty dialogue, poorly thought out dungeons that more resemble closets than proper dungeons. Lack of unique enemies(MMM adds mostly enemies we've already seen before). Quest design that is ludacrisly simple. World design that is bland, and unnatural in it's color scheme. Finally the world is still feels tiny.
Long answer, maybe, if you don't care about those things.
The main things that have been fixed, are, combat system, it becomes slightly better when you add DR, it's not great by any means but it becomes close to acceptable.
Beyond that, if you don't mind the pallete being mostly the same, UL adds a fair bit of marginally interesting terrain, that is restricted because of the fact that the engine SUCKS for doing interesting terrain, requiring you to make solid meshes, like the ones you see in skyrim, to do any hard/natural geometry that isn't rolling hills.
The focus of UL, is mostly on making more interesting forest terrain, which while an interesting endevor, there are frequently conflicts between the mods, because an author makes a mistake.
Quest design has been helped along by things like Integration, which suffers because it was written by a german person, so it has the standard, "This is not a native English speaking persons" mistakes.
Other than that, there's also Kragmor's Quests, or something like that, which suffer because they use a bunch of dungeons MMM/OOO modify and have the low level quests sending you into high level OOO dungeons.
The leveling systems been improved by Progress and a host of other leveling mods, my personal favorite when I played oblivion was nGCD, because it did the elder scrolls skill gain in an interesting way.
So if you can get over all that, it'll make oblivion improve from shit that forms the base of shit mountain, to the tip of shit mountain, the sole place where shitty mediocre games reside.
Oh dear, babies crying, time to feed the demon, or possibly change it.
