Imagine being able to set the maximum allowable build height to anything, such as increasing it from the default 35 feet to a more respectable 50 feet. This would allow some basic elements such as loops to be buildable above ground in this type of park. Conversely, it could be set even lower than the default for an even greater challenge. Another customization option could be the maximum elevation relative to the map rather than to the structure height (the actual height marker shown when building rides). This would realistically emulate parks such as Alton Towers where things can be built tall structure wise, but not tall relative to the horizon.
I would imagine these changes wouldn't be too hard to make, since it's most likely just changing a hard-coded "35" to be an actual variable