Space Opera, Humor, and Headaches

My sinus headache seems to be morphing into a rare migraine, so just a quick update: I’ve finished the third draft of my space opera story (working title Beowulf: In Harm’s Way), and Emily’s about half finished checking the first Slightly Off the Mark book, which we’re hoping to have out in April.

The space opera story is only about 55,500 words, and the humor book around 40,000. I think shorter is better with non-fiction humor, but what do you think of that length for science fiction? My novels tend to be short (and my short stories tend to run long!)