In my evil playthrough I'm currently at the start of the Temple of Shar - we've got in, met Balthazar, but not done anything else. I'm looking forward to the fight against Yurgir because I always found it really hard in the last game but a great achievement when I finished it. This time I think I can do some interesting things with Lightning Bolt. I don't know yet what's going to happen in the Shadowfell. Shadowheart doesn't like me much, so she'll probably kill Nightsong. I've wondered if I might side with Balthazar to retrieve her, but my character is looking to Minthara quite a lot so maybe not.
Meanwhile, I've left Balthazar to stew a bit while I go and investigate that weird bubble of light across the water from the mausoleum. I haven't decided yet whether to go in the front, try to sneak in the back (I'm not sure if there's a way round to the rear entrance with the mines), or not go in at all until after the Shadowfell