Yoop:
IMHO, the circuit ID at receptacles, etc. is a design/spec item. I can't cite anything within the NEC.
The spec for the hospital in my town requires circuit/panel ID on all receptacles, switches, data/comm jacks, etc. The data center also has the same spec, as do some other commercial locations.
I see where you are coming from with this, but...it may fall back into the 'qualified person' heading.
As to disconnects, controllers, etc., again, without an NEC article, that also falls to 'spec' or good trade practices.