Hmm, those characters are really... nice. Time to ruin them and make some fun!
Now, there are flaws that work and many that are just irrelevant.
One key ingredient to a good flaw - it moves the story! And before we begin, 'brooding' is not a strong enough flaw for any character, human or otherwise. There's a good reason viewers preferred Spike to Angel in 'Buffy the Vampire Slayer', he was bad.
This brings me to another key ingrediant - balance it with a good trait. Spike was funny, funny enough we could overlook the years of slaughtering and kitten consuming.
Here is how my NaNoWriMo characters are shaping up and problems I've had with character flaws.
My NaNoWriMo novel (which has now passed 50k - Yay!) is called The Costume Maker and began with an idea of characters. I first had two characters in mind, a gypsy woman who makes amazing costumes, is a bit magical and has a short temper, and a teenage girl who is completely rude, selfish and yet somehow, adorable.
Missy, the teen, is so rude to the gypsy woman, Rosa, that Rosa sends her to a magical world with Dragons and Fairies and magical Gypsies.
These two characters are working well in my story. Rosa is fiery and sentimental. Missy sees each experience in relation to herself, and is always looking for personal gain, she is also totally unaware that she has any flaws at all and wonders why people treat her as if she's stupid.
Next I needed some heroes to go and save Missy. I sent in her new almost boyfriend, Lance and a shy girl called Lucinda, that Missy considers a 'freak'. These two characters are the ones that will need a lot of editing in my second draft, they're just too... nice.
I've started to show Lucinda's shyness and feelings of inadequacy as a flaw, but it needs strengthening so there can be a bigger character arc over the story. A character arc is where your characters start out the story one way, but undergo changes throughout your narrative. Lucinda should be extreme in her shyness and self-doubt, and through discovering she has the blood of magical Gypsies, she will start to grow into a confident young woman. How can I use this to move the story though? Still playing with that.
Missy propels the story because her personality causes hitches in the heroes' attempts to save her. They find her in a Fairy castle, but discover Missy is actually reluctant to leave. More problems follow.
Lance is also a bit cardboardy at the moment. He's captain of the school footy team and is hugely popular, but I want to deepen him to be some kind of closet nerd or something. Again, I need to find ways to make this move the story, perhaps he can be a science nerd by heart and his knowledge helps them in a dangerous spot in the story? Or maybe his online gaming comes in handy when they actually meet a dragon? Food for thought.
I've also mentioned the need to balance flaws.
With our heroes it's usually the other way around. We start with their good points and then throw in some problems. With Missy I started with the flaws, I don't even intend to arc those much, I want Missy to stay pretty much the same right to the end. What I will do, is throughout the story, reveal great traits Missy has, like bravery and loyalty, that the others didn't know were in her.
Where can you find great flaws?
There's always the original sins. Biblical sins as flaws can add a deeper theme to your narrative as well as a moral.
Phobias can be fun flaws which must be faced for the character to progress through the narrative.
Everyone thinks I'm a very calm character, but the smallest things can freak me out:
Hairy spiders, flying (don't give me the safer than a car lie. If a car's engine dies, you just get out), balloons (waiting for them to 'pop'), milk that's been in the fridge for more than 24hrs, middle aged man in supermarket isle wearing a Superman t-shirt, identical twins (not the people, but the concept of one person splitting into two freaks me out) and hanging my clothes on the line (too hard to even explain).
If you must have a nice character - then go whole hog and make them really namby-pamby, then have a piano land on them, because that's what your reader will be wishing for.
Webs and blogs on character flaws:
Dark World - Character Flaws
This one has the most extensive list of flaws possible. You'll find one perfect for your story.
More about how to make your characters stand out, than flaws, but very helpful.
Men with Pens
One of the best sites to explain character flaws and how they work.
A more artistic approach to writing flaws.
If you know a blog covering character flaws, share it in the comments.
And, as with all things NaNoWriMo, the idea is to get the story told in November, it's easier if you know your characters up front, but if not, you can rewrite flaws and situations in your first edit.