Here is a little something that may help. We use these all the time at work (not this specific brand but similar in design).
The rack mounted equipment are all on sliding rails. The non-rackmountable gear are on sliding shelves. The cables travel vertically on 1 side of the rack (velcro'd to the rack), to their specific cable arm. Power cables are on the other side, also velcro'd.
1UCMA-137 1U Horizontal Cable Management Arm
2UCMA-137 2U Horizontal Cable Management Arm
http://www.racksolutions.com/cable-management-arm.shtml
The cleaner the cable management is, the easier it'll be to switch out gear, and air flow will be unobstructed.