oh man i would LOVE to drive in such an environment of dense jungles, crystal-clear blue water, pure white beaches.
Inspired by the pic of the lagoon-title:
While you are driving on a racetrack across a dense jungle, you see a tiger on the left side of your race track opening his mouth with its blood-stained tooth to roar like a wild beast which has killed uncountable animals yet just to satisfy his bloodlust. You have forgotten to breathe, you have forgotten that you are the second-last racer in this race, because you take a deep look behind a curve which you've arrived in a very few seconds where the nature unveils his true and yet very merciless & brutal face of a snake which is preparing to catch a monkey which is happily jumping to a tree with fresh, yellow-green bananas and is clueless about the fact that he has seen his favourite meal for the last now. But your hope of a beautiful nature isn't gone as you recognize a female, mature elephant accompanied by her two elephant babies. (But as you focus on the race again with a smile on your face caused by the beautiful sight of the elephant monther and her growing babies, the tiger which you've seen when you entered the dense & mindblowing jungle, surprinsigly jumped from his hiding place to take a mortal bite in the neck of one's elephant baby

)
Trackmania has always focused on the competitive aspect and will probably never ever start breaking this rule, but giving the atmosphere, the environment a bit more depth wouldn't be wrong, would it? Valley is a great example where you've introduced the astonishing birds.