Jon given the installation you describe you have 13 current carrying conductors.

This means a 50% downward adjustment of the conductor ampacity resulting in the need for 10 AWG 90 C conductors.

In the second version of the circuit the current carrying conductor count remains the same as the majority of the load is non-linear.

That is my opinion of the NEC rules.

From a practical stand point no derating should be needed in this installation.

Bob Badger
Construction & Maintenance Electrician
Massachusetts