Revisions as follow: #66 is an improved version of #21 as requested. Tracks look more like train tracks now. I also pumped up the color values a tad to make them a little clearer. #67 is a variation in red and yellow - I must note that this yellow has an orange hue because otherwise it would get lost in the background, and even so, I think it still does get a little lost, it looks weak to me.
#68, #69 & #70 are more stylized versions, which I like, there's more dynamism to them. And #71 is the same as
#68 only with a glare in the middle of the track to represent a clearer "transition" effect, I pretty much made this one out of whimsy.
Let me know how you feel about these last entries. Thanks again!
Cheers.
-Ed.