Going from Oblivion to Morrowind might be a bit of a shock. I happen to love Morrowind (more so than Oblivion) but I don't know how I'd react to the game if I've never played it before and had just finished Oblivion. For starters, the combat in Morrowind is strictly old school number based. It's like the game is rolling dice in the background to see if you're successful or or not everytime you swing your weapon. So you could be swinging and missing at some simple mudcrab until you build up some stats or are doing something out of your current class. And that's another thing - because everything is all number based, Morrowind forces you to actually role play within your chosen character's abilities. In Oblivion you could basically become some amorphous blob of a character and it really doesn't affect how you play. If you choose to be a thief in Morrowind, then you are going to be playing like a thief (especially early on). Don't even bother trying to wield a big ass sword 'cause you probably wouldn't be able to hit anything with it if you tried. I happen to love the number crunching going on in the background of Morrowind but it certainly isn't for everyone.
The narrative in Morrowind is there but it's up to you to find and follow it. It's much less straight forward than it is in Oblivion but, imo, it's also a hell of a lot better. You're going to have to do some research and read some books in the game to get the full effect - I found the whole thing fascinating. There's a ton of history but you'll only get out of it what you put into it. There's also alot more questlines in Morrowind than in Oblivion with more interesting stories of their own but many of the missions turn out to be of the "go here and kill this guy" or "go there and get this item" variety.
Graphically it's ugly but I prefer the world of Morrowind to Oblivion. It's like an alien environment as opposed to the European/renaissance fair of Oblivion. Sure there's no climbing a hill and looking out over the valley to watch the sunset like in Cyrodill but Morrowind has it's own otherworldly beauty. The people are butt ugly but they somehow don't seem out of place because of the bizarre design aesthetic used throughout the game. And speaking of people - they're all pretty static. They don't roam like they do in Oblivion. You see them at their assigned places during the day and then usually in their homes at night. I didn't notice it initially but after awhile it becomes all too apparent.
The best thing about Morrowind is that there's no fucking level or item scaling. Rare items are just that - rare. No broken game here...that is until later in the game when you basically become a god among mortals, but I prefer that over seeing a bunch of bandits with Daedric armor and brandishing enchanted weapons on every road.
