I don't think there's anything wrong with using blogger. I'm using it and it ranks well. If you do a google blog search,
my blog is in the "related blogs" section of search results for
Sales leads and for
business networking, two keywords that you would think are big.
But, you know what? Having top results for those keywords is quite useless. I barely get any traffic via those searches.
If you're looking for pure traffic, try writing eZine articles instead. Read my article about why it is better:
Writing eZine articles is better than blogging