I was very disappointed in not being able to join the twin lamps or the dark brotherhood. I realize the makers of Morrowind only have so much time and so many resources, otherwise the game creation time could turn into that of Fable, which we are all very upset
about. You know what I would like, though? always get so sad when I make it to the tippity top of the Mages Guild, Thieves' Guild, Imperial Cult, whatever, and I look back and go... "That was it? Is that all there is?" Haha sorta like Sims or something where all you need is job promo every day for 10 days and you're all set. Anyway, I would love to see the guild and faction missions expanded and increased. And ... You know what I keep finding myself doing in the tribunal expansion? I find myself in the Plaza Brindisi Dorom (I'm particularly pathetic in that I can remember all the random unimportant names like that) going up to the doors that "lead out" of Mournhold. And they never open. Not once.
I would love to see Elder Scrolls IV take place in yet another area, perhaps Wayrest or Cirodiil or Summerset Isle (Not that would be cool, I can picture all this shady glen type of land with all these High Elves touting their philosophies and arts.) Maybe several all together. I love how GOTY gives you the option of travelling between three different .. ummm... "continents". I would really like to see ES IV with that same wonderful idea... perhaps being able to travel between Wayrest, Summerset Isle, and Cirodiil, and having missions that make you go back and forth between them.
I also think things should be a little more pricey. I have never, ever had to stay in a town until I earned enough money to get somewhere else, not even in the very beginning. So, to travel from, say, Wayrest to Summerset Isle, instead of the Vvardenfell trend where it would be about $20 (if that) it should be like $300 a pop. Just like real life travel fare.