I really have to admit, that ES2 is a beautiful looking game and I love the different type of systems, suns and planets.

I imagine, that it would be an immersive experience if you could observe the changes of the planet once it's colonized by a race.

And with this, every race with his own culture will consequently leave a visible footsepts on the planet during the development of the colony. 

Like more visible city lights in a fully populated planet or visible smog above observable industrial landscapes on planets with reckless industrial exploitation. 

Such visualizations add more life to the game. It shows, that something happens down there and maybe shows concretely what the inhabitants are doing to the planet.

This is even more a logic step within the game as ES2 wanted to focus on population of systems.

I agree. 

I would also be cool if there was a visual degradation of planets that are being depleted by the Cravers.

There is already a thread about it here: 

https://www.games2gether.com/endless-space-2/forum/66-game-design/thread/20824-the-visaul-representation-of-colony-developement

Would be good to have these two merged :)

Oh thank you for the hint! :D Still need some orientation in the forum. I don't want to make double posts on things which are already here! ^^