Did I say anything about citys and dungeons? I only commented on the point about the landscapes. They were empty dull and boring to explore. Stay on point.
"Every time I play Oblivion after playing Morrowind I am impressed about the vivid landscape and all of its details"
Details. I'm filling in what makes up the detail of the landscape of Vvardenfell! Theres plenty of different regions in MW (looking at the large scale) and the place is seeped in places to explore. Yes, the game is old so the texturing isn't as good but come on.
(Copied and pasted from http://www.uesp.net/wiki/Morrowind:Places)
Ascadian Isles — A fertile agricultural region of islands and peninsulas in southernmost Vvardenfell.
Ashlands — A forsaken ash desert in the areas surrounding Red Mountain.
Azura's Coast — A mostly uninhabited region of rocky islands and peninsulas on Vvardenfell's eastern coast.
Bitter Coast — A swampy and poor region along Vvardenfell's west coast.
Grazelands — The pastures in northeastern Vvardenfell.
Molag Amur — A region of volcanic rock and lava pools in the southeastern interior of Vvardenfell.
Red Mountain — The volcanic mountain dominating central Vvardenfell which is encircled by the Ghostfence.
Sheogorad — A wild region of islands and peninsulas surrounding Sheogorad Island off Vvardenfell's northern coast.
West Gash — A rocky, highland region in western Vvardenfell that is rich in minerals.
Each region is distinct, and filled with places for you to explore. I'm sorry if you can't get beyond the aged graphics thats not the game's fault. Leave those of us that can judge the landscapes in terms of design and not texturing to our opinion.
Cyrodiil just seemed to be a field, with a mountain to the north and a swamp to the south.