There are gazillions of sites on the internet. It's getting increasingly difficult to not get lost in the crowd. If traffic is something you want to build, standing out is key.
On Problogger, Tom Treanor recently wrote Charles Darwin’s 12 Rules of Blogging Survival. He offers several ideas that might help you narrow in on a good strategy for you.
The bottom line is, the biggest mistake you can make is to find a blog you like and duplicate it. Don't just "do what they do." You absolutely must find a way to differentiate yourself from everyone else. Not sure how to do that?
Take note of the blogs you like. Get some ideas from others.
Then be funnier. Or be more serious.
Be more personal. Or be a better expert.
Be more focused. Or be more broad.
Be more organized. Or be more spontaneous.
But be more…you.