I think its more philosophical than an rubric for actual governance. The constitution was deeply influenced from enlightenment thinkers and basically the first of its kind that influenced the rest of the world.
Towards that end I would recommend the recently published book _America's Revolutionary Mind_. It provides a comprehensive (and sometimes exhausting!) overview of the influence of Locke and other enlightenment thinkers on the evolving mindset of the pre-Revolutionary war era. It's not just a review of well known names - but shows just how much Locke's ideas really reached a large range of the then every day royal subjects of the crown in the colonies.
Even with that - its still amazing we got something as good as the Constitution.
