Uncle Jesse,

I'll tackle the color issue. I prefer red iris with black pupil on a two tone eye.

Eyes on fish are delicate, even minor impact can cause capillary damage and thru bleeding in the eyes, thus they are one of the first places that will show internal injury. I beleive that bass (probably all game fish, but bass are the most popular of them) instinctually target injured prey. I think that the red eyes can be one of many 'triggers' that may help cause a bass to strike.

If I'm painting eyes, I'll ofte ndo a three part, yellow, red then black pupil...but I always use red for bass flies.

Seems to work so far.

Buddy