If you liked Florida, how about Port Aventura on the Costa Dorada?
Needless to say it's not on the same scale as Florida so you must go with realist expectations plus Salou itself is not everybodys cup of tea.
However, you have the distraction of the Theme Park and Water Park & Barcelona is an hour and 20 mins away by train, which apparently is a 'cool' city in most teens books. You also have Tarragona and Cambrils nearby. Having been to Florida, Port Aventura and Menorca, I would say lovely as Menorca is there is more for a 16 year old in Port Aventura. Menorca you would have to rely on him meeting other 16 year olds.
There is tons of info on the Costa Dorada forum