The gameplay and plot sucked in BG2...? Goodness, have we been playing the same BG2? I mean, you are certainly entitled to your opinion, but when you ask a question that derives from an acceptance of that statement, and the statement itself flies in the face of both sales figures and the consensus of CRPG players' opinions, you've got a bit of explaining to do.
BG2 has been the most popular and successful PC-based CRPG of all times. Gameplay-wise, it is a much richer product than BG1, offering--
a) A greater variety of quests (less of the purely FedX type)
b) More interesting party NPCs, often with their own, more complex quests than in BG1
c) Choices that allow you to take sides in major conflicts
d) A greater role for alignment (not that I like it, but it *is* there)
e) Far better movement algorithms
f) Less of the annoying, endless walking across empty wilderness
g) A more complex antagonist with a more interesting background and friends
h) More puzzles
i) Larger dungeons
j) Better map annotations.
k) A better method of tracking information
l) Much more dialog to make NPCS seem "real"
As for your question: NWN will focus on a single character, not a group. You'll have a follower or two, but they really won't be major NPCs as before. This is a deliberate decision, and one I frankly regret that Bioware has taken. Still, if they're doing the game, I'm willing to bet it will contain everything else that has made BG2 so justifiably popular. IMHO.