Design decisions for cabling will vary with the facility and actual
intended uses. For example, an Internet Service Provider with significant
telecom requirements may be designed quite differently than a hosting
provider.
Facilities where the design is not likely to change significantly are a
good candidate for "tidy cabling" of the sort under discussion here, but
where changes are expected to be common and frequent, there are other
ways to make it look nice, without investing a ton of time just in time
for next quarter's changes.
The best thing you can do is to allow for what might seem to be excessive
amounts of space for cable management, and then be prepared to spend TIME
when installing equipment or making changes. The biggest thing that any
serious cablemonkey will tell you (and I won't argue it!) is that the job
takes TIME to do right. Remember that the time invested isn't being
invested just to make it look good, but more importantly to make it easy
to deal with when something goes wrong. Good cable guys deserve a lot of
respect, for making it so easy to debug what's going on when something
goes wrong.
The design for your facility is best based on the unique situation present
at your facility.
... JG