Before I post anything about NWN2, let's talk about Kotor 2. I like Kotor1 more than 2, it's one of my favorite games. However, that is just ridiculous.
"what many consider as, Kotor2's terrible quality".
Not being as good as first one doesn't mean "terrible quality".
The UI is IMPROVED version of k1's one. Each time when playing K2 it's hard for me to get used to old K1's UI which is clumsier and worse. K1's UI is good, I never had anything to whine about it until K2 came out and showed me how it was hugely improved with many little tweaks.
UI is much better than K1's one, which was good to begin with.
"The plot's just terrible and incomplete"
Definetly incomplete, whole ending was cut, whole planet was cut, huge amount all other kinds of stuff was cut.
But please tell me how K1's plot was any better? It was copied from movies, had few little tweaks and changes and voila -there you have plot of K1. Whole "Revan revelation" was sooo awesome plot twist...
My problem with K2's plot is that it goes against SW canon, but if I manage to ignore that it's much better. It is original, villains are better (Malak the Evil Maniac was very, very deep antagonist), especially Kreia which is best written character in Kotors.
Before I argue anything I need to know why K2's plot sucked.
"Dungeons and challenges" doesn't differ one bit from K1 but the're easier. (Game being too easy is main reason why k1 is better IMO) And both games are mostly hack n slash, fun and entertaining but still hack and slash.
Graphic thing is most silly since both games use same engine.