Hi , sorry for the late reply.
There was a lot of fine tuning in rent prices and also in the migration flow algorithm. I'm currently updating the docs but this page is already with new information about the changes: https://microlandia.city/docs/migration
Regarding tax cuts for certain businesses, and disabilities, it's a very interesting idea. I totally see it happening soon :)
Regarding combustion/electric cars and other environmental aspects of the game, that's something that we're delaying for a mega-update in September that will be all about environmental factors of the game (pollution, carbon footprint, emissions, health problems due to air quality, etc.)
I'll keep you posted when I rewrite the section about rent of the website, and the section about economics, which hopefully should clear out all your questions.