Uuuuuuuuummm....no American "Colin"? How 'bout Colin Powell? I have a friend who's sons name is "Cullen" as well.
As for Reginald, oh, yes...we have them. We just call them "Reggie" (as in the ballplayer, Reggie Jackson).
I also know a Mavis, a Sybil (Sybil Shepherd beind a famous one), and a Zoe. I also know an Isolde.
You're right about most of it though. You won't hear most of those names often over here, if at all.
I think the names made it here, but as with the culture and accents, your side of the pond went one way, and we another.