Critique and Advice; the treadmill of adventuring.

I know this is an old thread, but I have kind of a question about adventure writing. Is there a such thing as taking your adventure too seriously? Back on the MSPA forums, I felt like I might have made the tone of my adventures too straightforward and boring, and didn't have enough of a sense of humor about things my characters said/did or funny suggestions the readers made, and the readership of my adventures always dropped off after the first few updates. Do you guys have any tips on balancing a "serious" tone without making it too boring?