Well, I took the Olympus out today and flew it with the 15x10 eAPC prop. Plenty of vertical authority with the prop and no problem flying a complete P15 sequence on a 4000mah 5S pack. I lowered my throttle curve a bit in the middle to compensate for the increased pitch so horizontal cruise was about the same speed as the 15X8. So, if you want to use a 5S pack instead of 6S it worked well for me. An increase of 5A going from an 8" pitch to 10" pitch doesn't seem to overload anything. The ESC is 70A and the motor is ambient when landing. It was cool today so higher ambient temperatures will obviously increase the ESC and motor temps but it doesn't appear that it will be a problem.
Woodie