Whilst I don't disagree with anything you've said.......... the OP was worried about the teenagers.
I'd put the RCL Flowriders, Abyss, Slides, Teen Club, Zip Lines, Sports Court, Mini Golf (granted it's a limited course) etc etc up against what other lines offer in this regard. (provided a ship with these options was available)
I would, however concede the NCL go karts seem like they could flag some teen interest!!!