Cool cool,
So maybe someone that sails royal can chime in, but *on carnival* they'll give you a second card with preferred name, and then you just have to bring the original with you when getting on/off the ship...not sure if royal does that though.
As far as teens go, no clue, my partner and I are both in our late 20s/early 30s but I can definitely attest that the kids these days are, pardon the pun, a boat load more accepting than when I was that age.