Re: What nickname would you use for Raphael?
A couple I know sometimes call their son Raphael "Rafi" ... not sure how they'd spell that. It approximately rhymes with taffy, maybe a slightly longer A - same vowel as in Raphael. I think it is the best nickname for Raphael.
Rafe pronounced RAYF doesn't seem like a nickname for Raphael, IMO, since it's basically Ralph and the different pronunciation from Raphael makes it seem contrived to me. Raf (rhyme laugh) would work, and no I don't think the term "riff raff" would ruin it. I think it sounds nicknamey. Rafa seems contrived to me, too.