Getting ready to pull the trigger on the ADA-1500 but I wanted to see what others' opinions are regarding the number of channels needed. I was considering amplifying all 5 channels and only running the in-ceiling speakers off of the AVR but is the extra power needed for the rear surrounds or would the AVR be enough power for them if the front stage is on a 3 channel amp?

LFR1100
VP180HP
EP600
M3 In Ceiling x 4
M5OW
M2 - Atmos rears
ADA1500.5
M3 Outdoor Speakers
ADA 1000.8