Actually CSS should have been included as an option. Since any type of presentational HTML should be avoided if possible. Centralize all of your styling in your CSS files and you have one place to change the look of your site. Decided that h2 headers on your site should be white with a blue background? Change one line of CSS to update your whole site.

Check this page for examples of applying lots of different style sheets to the same page: http://www.csszengarden.com/