I htink your grains per pound and FOC is OK. Unless you are having arrow flight problems, I'd leave them alone.

On the Magnus with bleeders, I can only give you my opinion. I think they are great heads, but with the bleeders, they are too noisy for me. Also, I have heard some bad stories about the bleeder breaking off when encountering bone and stayining the animal. Could make field dressing a bit of a pain.