Well, it certainly looks better with the color-cycling (I'm assuming) landscape stripes than just one solid color. That makes a big difference to me in how it looks in lieu of different color road sides.
Though I'm not a fan of the style of art you are using, it's too Nintendo cutesy-kid looking for me; I'm expecting Mario to come racing up from behind in is go-kart. I'd try to stick closer to the Master System's graphic look.
The Master System has too many details and remember is in 1:1 ratio with lots of colours. It's impossible to get it on A8.
Only thing I have in mind to do and show, probably, like I said, not today but by tomorrow is to have also the sides ground in different colour(s) but using this same method.
On A8 and C64 with 2:1 ratio and 3 0r 4colours per char you'll always have something similar to this.
And if you like (it seems you don't then I could still replace the Ferrari with Mario and his kart ...