Kethric, hardly a side character, but a worthy foe with plenty of set-up.
Oraj, a seductress character with convincing VA. Why no fling option?
Wulbren, I can appreciate his potty mouth and hate-filled drive - tied to events in BG1.
Did like flirty Lakrissa, but turned out just a tease. Disappointing.
Rolan, has some wild mood swing drama and difficult to get his happy ending.
Volo, useful and with character. An actually welcome camp follower, unlike the rest.
Many, if not all of the goblins. VA and distinctive lines for every one of them. FR is a bit poorer for their loss.
Don't like plot armoured NPCs unkillable outside certain cutscenes. Sorry, but that is not a TT experience. Still, only a few and largely ignorable.