Yes, changes in drag will change AoA. Reduction on the bottom will cause a slight nose up. And changing the angle of the engine may have a benefit, but it will only show in testing. Windmills actually work better with one side facing further into the wind, because it reduces tip vortices on that side. Forward sweep greatly reduces tip losses. But for a prop going a hundred times the RPM? I do not know. What I can say is that the blades being reclined backwards during high AoA is almost certainly not good for thrust.