I would build the park in one of two ways.
1-according to habitat. house all the tropical animals in one part, the dessert animals in another, and so forth. also reate the atmosphere of being in that type of climate. like if you are in the 'tropical' section u should feel the heat and humidity that the reptiles experience. heat the entire building or whatever and have misters and foggers. the same with the other 'regions'. the dessert part has got to be hot and dry as hell etc etc
2-house the animals in sections from their country of origin. shape your building and cages according to the continents and oslands they come from. hard, but something different
i would stay away from 'morph' and focus on natural animals. or have a complete seperate area for the exotic exotics.
if u want to be the coolest park in the world... get some marine iguanas!!!
o, and no reptile park is complete without ur standard komodo dragons...