That's pretty gorgeous, Ezer. Admittedly, reproducing an accurate representation of the Martian sky is a pretty tricky matter. Wikipedia has an interesting article on the subject. During daytime the sky on Mars would actually be pretty bright with no visible stars. According to Wikipedia, it is now known the color of the Martian sky during the days is a scarlet or bright orangeish-red color. However, I don't know what "now" is supposed to mean since the claim has no reliable references to that supposed discovery whatsoever. Eitherway, I'd imagine orangeish-red would be the way to go. Yet, as Mars is referred to as the red planet, an ascetical tint of red would give the player a more classic impression. Sunset would be interesting. While the sky would be rose, the sun would be circled by a fade of blue due to water ice particles. Twilight would last about 2 hours longer than on Earth because of high-attitude atmospheric dust. Some technical details is the Sun would be an 5/8 of it's regular size. The daylight would be about half as bright than on Earth. However, that doesn't necessarily make the environment half as bright. As the thinner atmosphere of Mars results in less light scattering, it would more of increase the contrast between the sun and the sky, making the latter appear darker. So yeah, depicting the Martian sky is surprisingly complicated.