Firstly, I must apologise as I know that this horse has been beaten to death so many times already, but now that I've actually played Oblivion, I have to throw in my rant amidst the masses (actually joined up here just to do that...)
I've played Morrowind, Arena, Daggerfall, and now Oblivion. I'd say my order of best to worst is: Morrowind > Oblivion > Arena > Daggerfall. I play a mod heavy Morrowind (though I can still enjoy vanilla provided better bodies is installed as I've been too spoilt with modern games to be able to stomach the standard body meshes). I played Arena and Daggerfall when they were released for free. Arena I enjoyed for what it was and once I got into it it was fun. Daggerfall I don't remember much except that I finished it and don't really like it now if I try play it.
I've been a bit iffy about Oblivion as there are so many positive and negative views on it, but recently it went for special on GoG right on my birthday so my wife got it for me. I loaded it up with excitement and expectation which quickly turned into disappointment.
I spent a while looking up and collecting mods and eventually ended up with: the Unoffical Patches, Mark ad Recall, Unique Landscapes, Weapon Expansion pack for Oblivion Nthusiasts, Oscuro's Oblivion Overhaul (OOO), Dynamic Map, Natural Environments, and Alternate Start Revamped. (I recently added Perfect Working No Quest Markers, Disable Fast Travel, Ferry, and Stagecoach to try fix some of the issues I still have with the game.)
Okay, so onto my issues...
1) STARTER DUNGEON - This was a really long and painful process. Done once, never want to again. Alternate Start Revamped takes care of that (as well as prevents the main quest from being immediately "forced" on me) but does kind of break immersion when you tell Martin that his father told you he was his son when you've never even met him, just found a dead guard with the Amulet of Kings and a Note...
2) MAIN QUEST - I actually don't have any problem with the main quest itself except that I feel "forced" to do it. Kind of hard to enjoy the game when everyone is acting fine and the world is supposed to be facing a disasterous and imminent end. That and the Oblivion gates got really really stale after the second one...
3) LACK OF DIRECTION AND QUEST MARKERS - So many times I couldn't find someone or some place in town due to having not been given any directions only to remember I had a quest marker. Think I prefer being lost to having quest markers though. The quest markers made me feel like the game was being handed to me and that I didn't really have any say as such.
4) COMBAT - I played with a straight up melee/archery concept. I disliked both. In melee, even with a Daedric longsword I found myself having to hit enemies SOOO many times before theey would go down. That, and having enemies charge me with a pile of arrows sticking out of their chests, just broke combat for me. I don't know if Vanilla combat without OOO is better or worse, but for all it's flack and frustration, I actually HIGHLY prefer Morrowind's combat. Even though you missed most of the time at lower skill levels, at least opponent's went down quickly when you could hit them.
5) DIALOGUE CHOICES - This also really irritated me in the main quest. My choices always seem to have been made for me. For example, when brining back the Amulet of Kings (that or the Greater Sigil Stone - I don't remember which) to Martin, the conversation (abridged and summarized) went something like this:
MARTIN: Thank you for doing this, my friend.
ME: I had a choice? (Other option was pretty much a "here it is, take it")
MARTIN: Of course. You always had a choice. It was freely yours.
ME: Well, here's the stone. (Only option)
MARTIN: Thank you, my friend. Now take me to the temple to light the dragon fires.
ME: Yes, my liege. (Only Option)
I feel like my whole experience in the game was like this. I Morrowind you could pretty much refuse anything - but not always. You couldn't refuse entering the emperor's service when handing over your paper's in Balmora - but I've got a mod to fix that
. Sure you could say yes and then just ignore that you did, but it's not really the same thing. Also, almost everyone seems to have nothing to say...
6) TRAVEL - My only other main complaint is the fast travel. I would have much preferred having fast travel via in world systems (which I've sinced fixed with some mods - though it puts me off that the stagecoaches have no horses to pull them...
Anyway, there are lots of things that put me off this game (like being able to ride a horse but not fight from it?!?). I don't know how to describe it. When I play Oblivion I feel like I'm playing a game. When I play Morrowind I feel like I'm part of a world.
Now, to the title of my long rant. Oblivion Isn't Morrowind. Yup. It isn't.
When I stopped expecting Oblivion to be like Morrowind, I began to enjoy it more. I could enjoy it for what it was (and what it isn't). To me it feels like a open-world Fable (for those of you who know the game). I know that's probably one of the worst comparison's but that's how it feels to me, and there's nothing wrong with that. I actually enjoy Oblivion. Will I play it for long hours and sink months and months into it? I doubt it, but who knows. Is it good for a quest quest or dungeon when I'm looking for a quick (but not too quick) relax? Yes. Definitely.
TLDR - Oblivion isn't Morrowind. Morrowind is Morrowind. Oblivion is Oblivion. Comparing them doesn't work. Going into Oblivion expecting something awesome while holding it up to "what it should be" or "what it needs to provide" already sets it up to fail. But playing it for what it is, without expecting anything from it results in a rewarding and pleasing experience.