I don't care for
Rudolph and am lukewarm on
Rudy and
Hector. I like
Simon well enough, though. I think even in a sea of -n names, I wouldn't lump
Simon in with them. It'd be like throwing
Peter in with occupational names ending in -er: it might have superficial similarities, but the impression it makes just isn't the same.
On a side note, have you ever give thought to
Nestor? When
Nestor or
Hector come up, one will usually remind me of the other.