Well that's nice idea, but selection of pins to where you can map HPWM - is quite limited as I know.

I had another idea - use MIBAM as is, but feed outputs to logical AND gate and use built in PWM generator to "chop" these outputs for better resolution. However, in case of 48 outputs, this will require 12 additional chips (considering that 1 chip is 4 AND gate), making such implementation less practical.