Variety is the spice of life so spice up your blog now and then.
A new blog should not add to the existing noise in the blogosphere. Do something outstanding to get noticed.
Add your personality - If you are writing on a particular topic, there are a number of people who will be writing on the same topic. So you need to add that specialty to your blog to make it look different and to allow your readers to take away something that the others are not offering.