Great exercise you start to write about things and way of thinking you'd never do or like... you don't need be that girl just write about her...
I agree about the cliche character you describe in http://jocelynlily.com and lastly all is sent in that direction so... its boring.
Regarding the other topic the thing is people who read books wants a good story: action, with politician background, based on lawer, police characters... or fiction based in history... and if those stories have a deep sexual background people found them always interesting.
So... you have a look in different places where books are sold... look them how they choose the sections for topic, you make a small study of that...
and... you will have your winner topic.
Of course now we are talking about earning money.
So i'd put more efford in choosing a winner topic and... distribution and publishing.
As more people you can send your text the more probably you sell...it seems obvious but...