The main difference about this park compared to other parks is that building on water is more expensive than building on land. This can also cause trouble when you want to rely on pre-built rides if they are too high. When building roller coasters that can not have very tall supports, it is a good idea to build near the land, since it is shallower. On the other hand, being close to water increases the excitement rating of your roller coasters and the water isn't too deep, so altogether, you should be fine.
In order to win this scenario, build a typical theme park with a variety of rides and advertise to get the 1,300 guests.