Like Commander O'Donnell of the Demeter. He was a really cool character. The hallucinations were a bit much, but aside from that I really liked his gentle quirkiness, and the surprising effectiveness he revealed in spite of everyone's expectations.
He reminded me a bit Dr. Rush from "Stargate: Universe".
All in all, I really enjoyed O'Donnell, and I hope we get to see more of him soon. On the one hand, I realize that might not be likely, since there are eight ships to cover and he's not in the one that's going to be in every book, but on the other hand, his actions in the book did create a loss in the fleet that can be resolved on-screen as well as off.
I thought the thread with Drafar was resolved a little abruptly, but I suppose it was more about showing B'Elanna's parenting than his cultural conditioning.