I'm getting ready for a new case (same system, but got the Lian Li V1020R), and have a few things I'm doing.
First is using micro velcro ties, and those little mounting points with the sticky back in specific spots based on a drawing of planned cable routes.
Second is cable sleeving. I got stuff from performancepcs.com (individual sleeved cables) which will help keep everything looking clean.
Third, is time. I'm planning on this weekend spending a few hours working on cable layout and routing.
Finally, and more long term, I'm going to get sleeving from
http://en.mdpc-x.com/ (great looking sleeves), and sleeve things. I'm at work, so I can't find the actual picture but it's in this thread (
http://www.xtremesystems.org/forums/showthread.php?t=202639&page=83), and somewhere around that page. Basically it shows a PSU that has been sleeved from where it is output, starting off with all cables in one group and gradually breaks them down to eventually the individual cable. Here is a sample of the end. If you then imagine that 2-3 of these get bundled together in a sleeve, then 2-3 of the large bundles get bundled together you'll have an idea of what I'm doing.