Finally getting back to this project after quite an absence. Currently working on getting the design of the 2kV power chain completed. Also taking the time to learn KiCad. A screen shot of the PFC board is included below. New PFC design boasts 400V @ 2.5A output with 220VAC input. Input EMI filter and output 8800uF capacitor bank are off-board. The switching frequency is 100kHz, and the circuit utilizes polyphase switching to minimize HF ripple and noise. Loose output voltage regulation is achieved through cycle-skipping, which preserves both the high power factor and the high efficiency of the PFC: 95% @ 1kW, 91% @ 250W. The design does not require discrete heat-sinks and uses steady airflow to maintain optimal temperature.
The 15V power plane is hidden in the image, but it has the same footprint as the ground plane. (green L-shaped layer)