Camelot has a great score, a great first scene, a great last scene and the rest is pretty dreary and sort of...well, dull. It isn't unwatchable by any means, but the "there" that is "there" isn't "There".
If Gueneviere doesn't get a bunch of laughs particularly in Act One, then there is something wrong with the director. Lancelot is pretty, but what a stick in the mud.
Morderd and Pellinore are the only continually fun roles.
"If my life weren't funny, it would just be true. And that would be unacceptable."
--Carrie Fisher