With all the health hazards that come along with bigger airplanes that you claim, why shouldn't you get paid more to fly it? If there are no incentives, younger junior pilots would be forced to fly them and would end up getting older and unhealthier faster.
"From each according to their ability, to each according to their need" Karl Marx
That's what your blended rate sounds like and it's no wonder PCL agrees with you.
Ok, that was funny. Now if you'll excuse me, I need to go read the Daily Worker.