Spent a good two hours at this and still respeccing.
Mainly, I've swapped Beast and Red Prince over. So Beast will be a warrior which I think works better as he's always standing at the front when battle begins, and I've also given him one point of scoundrel and the pawn trait so he can still move around a bit.
Red Prince is now a rogue, with the enhanced mobility he might have more opportunities to do useful things with fire breath. And I've given him the torturer trait so that and chloroform is useful too. In general he should be as effective as Beast was if not more-so
Lohse I've mostly left as-is as a Summoner but with some points in necro as a second class
Sebille is still a ranger, I've given her the leech trait as she's always standing in a pool of blood thanks to flesh sacrifice, and I've given her the increased range and torturer traits so she can make more use of elemental arrows. I've given her a couple of points in hydro which should give her access to some heal spells I think.
I don't know if I'm done yet, but I think that's mostly where I'm headed.