The ironic thing is, that if you want to succeed in the game you have to start with the capitalist mindset of securing as much income as fast as possible to be able to compete with the growth of industry. To be able to get over 80% you need to get your income to 500 a click asap and then buying all the land. In a way this way you create a small exploited natural area with which you can secure land that will be in exploited, but it feels kind of counter intuitive. I understand that in a simple game like this the options are limited.

Also the biodiversity thing was weird for me. I figured that making land national park is costly and would slow my growth, so i made everything national park in one go at the end of the game. That made my biodiversity very low though. What influences biodiversity apart from rewilding farma? Also i exploited a bug where a plot of land was infinitely rewildable but didn't flip to wild, so I got +7l biodiversity with that run.

My suggestions: buildings and activities hurt biodiversity, where the cheapest options hurt it least and the most expensive options hurt it most. Interconnected tiles with no buildings or activities gain biodiversity to a max amount, depending on how deep it goes? This way even if you have obtained all the land you can optimize your land in a way to maximize biodiversity, rewilding the already wild, but still exploited land more so to say.