Blog theme with best SEO value?

Is there a listing of blog themes with the best SEO value?

I have three wordpress blogs and I use three different themes. How can I tell the most effective SEO theme? Does the theme really matter. They all have the “All in one SEO pack”. Here are the three blogs:

http://www.millvalleyhomesforsale.com (Green Park 2)
http://www.tiburonrealtor.com (mono-lab)
http://www.sananselmohomesforsale.com (Lightword Theme)

Also, if I had all of these with the same theme would it hurt SEO at all if they could potentially compete within the SERPs?