IMO, it depends on your goal, Mike. If your goal is to have a higher probability of reuse in the future, then cut them all long. If your goal is to have a nice, clean set-up for your current system, then cut them all to length. I've gotten the impression that you can afford to buy new cables (I don't know what would give me that idea
), so I'd say do whichever you want.
Personally, I wish that all of my stuff was wireless.