I would caution against judging any platform by how it looks out of the box. You might try a theme like Thesis ($$$) or the less flexible, but quite capable Flexibility3 theme (which I think has a freemium model).
I think a lot of CMS do blogs quite well - Drupal, ModX, a zillion others. But I think that "heavy" feeling of a page generated by a system tends to be more prevalent. That said, if you put some energy into your theming, most of them can look any way you want and several have mechanisms that easily allow for "context" meaning different sections of the site have entirely different themes.