I was thinking about a 2D survival game, such as 'Rimworld', 'Don't Starve' or 'One Hour One Life', but with an actual ecosystem and where your actions affect the balance of the atmosphere and the balance of the ecosystem. This combined with an explorable universe, how awesome would that be??

That would be pretty awesome in my opinion! Enjoy learning about game development, @samve. It will be cool to see if you will be able to make your dream game down the road :)