Lae'zel's Origin has enough unique dialog going on to make it worth it's own run. I've had a lot of fun with it and it's a little better than a Gith Tav in some ways.
Karlach is fun. Though I feel like I'm missing out on most of her story and personality by playing her as main, since they made the main almost a silent protagonist compared to Divinity 2. :/
I decided on only having a party of prefabbed characters, which I like. There's a nice weave of narratives, main character aside (aside from the occasional frown or rare smile)