waf: I did play Morrowind. It was the only game which caused me we to ask for 3 weeks of my life back. Don't get me wrong - I enjoyed parts of it... but for a supposed open-ended RPG, it failed pretty badly. Sure, there was a large land mass to explore, but how much of that actually contained encounters? And how many of the encounters contained any sense of depth which differentiated them from the others just like them? And the storyline was pretty linear and unimaginative. And what was up with the dialogue? You clicked keywords and that was it! I adored some areas, though. The swamp/forest areas, as well as a few dungeons and dwarven ruins, though again they got repetitive after a while, and they could have done so much more with the dwarves storyline!
Regardless, I am looking forward to Oblivion very much. Bethesda seems to have a knack for making real improvements on their past games, and they also seem to have made a decent dialogue system for this game. I suppose I'm also being hopeful because they are responsible for the development of Fallout 3, and if Oblivion is great, it is likely that FO3 will be.
Anyway, as for NWN1: I disliked the game graphically. Compared to something like Morrowind or even its isometric predessessor, Buldur's Gate, it felt pretty comical and repetitive. And that was actually due partly to an engine limitation. If you'll take a look at NWN2 screenshots, you'll see that it looks as good as Morrowind or Oblivion - thank god. I think the lack of variability in tiles lead partly to my inability to enjoy the dozens of underground areas quite as much as I would have liked. I'm normally a big fan of underground areas - as long as each one is largely unique (both in purpose for existing, and in graphical detail). A simple matter of quality over quantity, I suppose. Anyway, graphics aside, I got pretty fed up with the henchmen. Compared to games like KoTOR, Baldur's Gate, Fallout and the master-piece Planescape: Torment, the joinable NPCs were woefully one-dimensional and boring. Their quests were all unoriginal fed-ex, and their personalities were for the most part pretty bland. And what PURPOSE did they have to tag along? Oh, they had one, but it could have done with a healthy dose of creativity. Having said that, I enjoyed Shadows of Undrentide a lot more, and I suppose the majority of this rant applies to the original campaign of NWN.
The strange thing is, Bioware did NWN and KoTOR at approximately the same time, and used the same game engine and rule set. Why they were worlds apart I do not know. Surely it is due to something more than the setting?
Anyway, to answer your question, Laz: I think Planescape: Torment might fit the bill. I don't exactly know the breadth of your tastes, though, and PS:T is a bit quirky (but supremely awesome, IMHO), so...
PS:T is based in the Planescape setting, and the first half of the game mainly takes place in Sigil, the city of doors which houses portals to all the different planes, such as Baator, Faerun (where NWN is set), Elysium, Negative Energy plane, etc. The second half takes place in some of these planes.
I also thoroughly enjoyed Fallout in terms of plot and characters. That game is trun-based isometric, and slightly out of date graphically, however (1997). Though I'd still say it is my favourite game of all time. Fallout 2 is a very nice sequel. Oh and it is post-apocalypse sci-fi.
And Blizzard has split up. The Blizzard you see now is not the same group that made Diablo 1 and 2. That group is making Hellgate: London, instead, so go take a gander at that. That is 3D, though.
Speaking of 3D games, have you guys played Deus Ex or System Shock? Deus Ex falls under the genre of RPG, however System Shock doesn't really. Either way they are both awesome games. Again, sci-fi.
Um. Sorry for being overly verbose.