Are you gonna replace La Venta
Tzintzuntzan would be a nice candidate.
Are you gonna do a Mochica civ?
Mochica would be an interesting civ to do. Maybe I can do it when I have some free time.
Sorry but to put it simple this "history" is all made from very biased and unprofessional sources. Olmecs still are an archeological culture whose script is far from be decoded.
I did Olmec just for fun. As I said, most of the things there are speculative.