My family consists of two daughters (17 and 23) and my wife and I are 50. We enjoy all types of physical activity which is the reason we opted for the Liberty 7 day cruise versus the Carnival 8 day cruise. Carnival was less expensive but didn't have the flow-rider, ice skating, boxing ring and rock wall. We have cruised 4 times on Carnival and this was our first Royal cruise.
The day before we drove to Miami and stayed at the Hyatt Regency Miami, 400 South East Second Ave, which is a 4 star hotel. Got it on Priceline for $70. Great hotel and location. Do Priceline starting at $50 and work your way up and you might score it for $60. The hotel was 5 minutes from the ship. There is also a free public rail service right off the hotel to take you to the Bayside mall which is way more than a mall and has free entertainment, good restaurants, etc. We enjoyed the Bayside. We ate at a restaurant called Knives I think which served Latin food, all you can eat, where you can get different meat selections from chicken, steak, pork, etc. freshly prepared. I think it was around $20 per person and includes an ok bottle of table wine per person.
The Liberty was fully booked for this cruise so I expected, crowding, massive lines and sold out venues but with the exception of ice skating it never happened. What a really pleasant surprise.