It is never a good idea to take oneself too seriously. I believe it brings on all sorts of health problems. You know, like hair-loss, clogged arteries, ulcers, tanorexia, turning into a Prawn (anyone seen District 9?), that sort of thing. I like to have a laugh at my own expense at least once a day. My cat has a laugh at my expense just about every hour I'm home. And then she gets confused and thinks my toes are her kitty treats and tries to eat them.
This is also a philosophy I try to apply to my writing. I look at it, every so often, through the lens of the ridiculous. The fun-house mirror, if you will. Except reading text in a mirror is a little awkward. It makes me go cross-eyed. But I believe that a book that takes itself too seriously will become the most ridiculous thing--and a sort of ridiculous that the author has lost control of.
I would much rather you're laughing with me than laughing at me. Though I'd much rather you be laughing at me than, say, egging my house or my car (which has happened to me! Let me tell you, it was in the summer, and I didn't go out to my car until midday--so I had FRIED egg all over my car. That car is now, unfortunately, deceased in a car wreck that was not my fault. RIP.)
So I look at my manuscript and I laugh that I pulled all of this stuff out of my brain (I mean really, there MUST be something wrong up there...), and then I insert comic relief. I like comic relief characters. I also like dialogue lines that point out how ridiculous everything is. There are a few of those in my stuff--always will be. Because isn't that how life is? You've had a day that was SO bad, it was funny that that much bad stuff happened to you on one day? That happens to me weekly. At least I get a laugh out of it. And it becomes fodder for my manuscripts. Or it would, if I could ever be pried away from my fantasy worlds and write a story applicable to real people.
Now, please excuse me. My cat has just commandeered my left hand. She thinks it's dinner. I must open up negotiations for its return.