Your blog design must fit your brand and represent the calibre of work you deliver. Otherwise, you're using a bait-and-switch process that will only hurt your credibility when people discover you're not the professional that your blog and website present to the world.
Make sure the topics of your posts are also consistent with your brand. Don't blog about your relationships unless your business is helping your clients navigate relationships! Likewise, if your brand reflects sophistication and polish, use that tone when writing your posts.
Even if you have been blogging for a while, taking time to approach it more strategically can make it—and your business—more successful. See my blog post Your Blog Needs a Strategy to Succeed.
Need help blogging for business? I offer a one-hour consultation to evaluate your blog and give you recommendations on how you can use it to drive bottom-line results. Visit me at One-Hour Consultation.