Uh, we have no information regarding whether places like Beregost, Nashkel, Candlekeep, or say the Friendly Arm Inn will be added to the area near Baldur's Gate. The original game also had a settlement called Ulgoth's Beard, that was added in the expansion. I think it would be a good way to make connections to the original games, since Larian wants to make 'meaningful connections' to the original series.
These areas were not too large, Beregost was the largest, just a few quests between them really. However, I would be surprised it none of them made an appearance.
