I've been looking for a mod that would extend the big part of Morrowind's general tombs, caves, Daedric ruins, etc. Not randomly generated (I've found those). I just find the vanilla dungeons unchallenging and unrewarding, Less predictable, intelligent traps, etc... Is there a mod like that?

Darknut's GDR would be right up your alley.

Yes, that mod is great and actually it was after playing it when I realized that 90% of the other dungeons just felt so boring and repetitive. Therefore I am looking for something similar, but for more widespread. If there isn't anything, I may just play with CS and try to make at lest few "XXX Ancestral Tomb"s more unique