RE: Will more powder mean less drop?
It don't matter how much powder you pour down that barrel. That bullet will hit the ground eventually. So no, more powder does not mean less drop.
Serioulsy, you already got your answers, above.
As long as you're using say at least 70 grains of powder, find the load that optimizes your rifle's potential. I increase the load until accuracy starts to fall off. With my .54 Renegade it was 110 gr pyrodex.So I settled on 100 gr. Then I sight in for 75 yds and shoot groups at 50 and 100, just to see where it hits. If I aim for the center of mass, top to bottom, on a deer that gun always seems to make a big hole in the kill zone. I don't even think about aiming high or low, but I also never seem to shoot over 100 yds.