I agree, make all your reservations online, before you board. Reservations open sometimes 90 days in advance, start checking then, altho it can be 60 days out so dont get frustrated waiting if you see that they are not opened 90 days prior to your cruise.
The only Bar to have a cocktail at where you can see the ocean is Viking Crown Lounge.
Go to the Flow Riders early.
Izumi is excellent, so is Chops.
Park Cafe is a must for breakfast and lunch- dont bother with the buffet on Oasis.
Johnny Rockets also serves breakfast.
If you are a Crown and Anchor Diamond member, dont miss your invitation to Sail Away from Labadee on the Helipad, this will be the only time you will have access to this area. The helipad is closed to passengers on Oasis.