According to his interview in STARLOG (June 1990), Paul Carr loved doing WNMHGB, thought it was a fun job, and thought the show would be a winner. And he was very unhappy about being killed off.
I guess he wasn't that crazy about his recurring role as Clark on Voyage? He did come back in the 2nd season of that series as benson and got killed at the end. Poor guy never catches a long term break. He did a few episodes of Buck Rogers, too.