Bones is an okay starter but if feels like a more thrown together bundling of the latest and greatest of the web development trends (320andup, sass/less, html5boilerplate) than a functional starter theme. But at least it follows the wordpress coding guidelines unlike roots.
Question for those who understand open source licenses can this theme even be licensed under the WTFPL considering that it uses wordpress provided functions like (get_header and wp_enqueue_styles)?
: https://github.com/Automattic/_s or http://underscores.me/
We actually replaced the 320grid and other styles with Bootstrap because of familiarity with the framework.
Or you have the Roots theme if you are willing to break some wordpress conventions for cleaner code as an end product.