At what point did you register your project as a business? When you did register, what type of business did you register as and why?

It's always up to you to decide when to register, few clients can wait for two weeks before you register. My personal choice is an American C Corporation. Clear rules, many good lawyers, no need for a nominal director, easy to manage when you are remote. Some people may complain about the net income tax, but it's not the case if you pay everything in salaries or have marketing expenses.

And the net income tax is with 21% not that high if you compare it to some EU countries like germany with around 30%