I use black feathers. 4" on my hunting arrows and 2" on my 3D arrows. Cap the back end with black nocks. Are they hard to see? You bet. That's why I just follow through and not look for arrow. I know where it's at by remembering the sight picture at the moment of release. The best shots you ever make will be the ones you don't see. And if you don't miss you don't have to hunt for them.
Aim the bow. Shoot the bow. Let the bow shoot the arrow. And then keep on aiming.