Wow! That's a heck of a question. I'll respond in kind, but I give you fair warning: You probably won't like some of the answers.
First: Completely separate the "thrill rides" section of the park from the "animals" section. Make the dividing line clear and easy to cross, but also have a neutral barrier of clear space between the two. This way, visitors have an easy and clear choice of what part of the place is most interesting to them, and the folks who are more interested in the 'animals' section don't have to put up with the noise and crowding on the 'thrill rides' side.
Second: Enlarge the whale habitat. Get rid of any SeaWorld-like "theming" in the shows, to be replaced by a balance of education and entertainment. For long-term goals, look at establishing a whale 'rehab' center, with an eye towards training wild-caught orcas for return to the wild. This would follow an ultimate goal of eliminating the whole idea of orcas in captivity.
Sorry if that bothers you, but there's just too much we don't know about their social structure and how wild captures affect it (and them).
Third: Establish a well-designed interactive dolphin exhibit, preferably including a swim-with program which emphasizes quality of experience (for both visitor and animals) over quantity of people through the sign-up queue.
Fourth: Open the doors to cutting-edge research, mainly the possibility of creating a synthetic language to establish two-way communication with dolphins, whales, or both.
I realize this may sound crazy to some, but -- at least one researcher has already made some pretty good strides in that direction. Specifically, Lou Herman, at the Kewalo Basin lab in Hawaii.
I would want to see how far such an idea could be taken. I would also want to see what application of contemporary computing power, and digital signal processing techniques, could do about establishing, once and for all, if cetacea do have a structured language AND, if so, whether it can be decoded.
Crazy? Maybe. But riddle me this -- How many billions of dollars have we spent on projects like SETI (designed to search for signs of extraterrestrial civilizations in the form of their radio emissions), or on other deep-space exploration ideas? Seems to me we may have a lot of the answers we seek right in our own back yards, so to speak.
Even if it still sounds nuts, ask yourself what's more nuts: Starting multiple wars with each other, which nobody can win, or trying to determine if we really are alone (or not) in terms of intelligent life?
Happy travels.