So,.. Ladys and Gentlemen.
Didn??????t find any pictures so i only can imagine the mess of steel in this park.
deere839 ask me if i can help out.
Seriously, 27 coaster, 2 water rides, a bunch of flatrides AND scenery won??????t work on the systems today. IF you plan to make it available for everyone even the laptop workstations

Even with a hyper worm hole optimization.
To split the park into small ones is one solution. It also give the possibility to work on seperate pieces from time to time, which is a good thing.
Personally, i??????m not a great fan of this. I didn??????t liked it neither in my RCT3 career where this technique was used for bigger parks, like Disneyland etc.
In my opinion, you could concentrate on ONE aspect of the park. So if it is called Thrill Zone USA, it should deliver this Thrill very well.
A fine selection of unique coaster and attraction would be nice also you have already the design for all the scenery stuff.. it shouldn??????t be look like western... or themed like disneyland.. it should give the feel of speed and excitement. Modern architecture or similar to real things, like racing.. skydiving,.. bungee jumping and such things. It??????s all already there. That??????s my opinion. It??????s not done with 100 of coasters which are only different in theire style.
If you have done a selection of types, you want in that park, think of unique ideas.. what could make this ride different from all others! How could you present this ride to the guests and how could you embding this ride into the scenery/park.
I recommand to have maximal 4 coaster in that park. maybe 8 flatrides and one water ride.
If you put the flatrides in, make sure the flats are okay and well optimized. Maybe it??????s a good idea to make them simple and not too detailed, or detailed and with a lot of clipping and LOD??????s.
But: As larger the project is... so much more you have to think about every single polygon and count of objects.
In my opinion, clear the area, sit down and relax and think about the idea to have a compact but well working park =)
I hope that will help you to getting started! =)