I think the lead line will sound better if it sustains a bit more and is a little bit less detuned.
I like the rest of it a lot. It really has that melancholic sound to it, especially in the breakdown at around 3:00. The breakdown is excellent and so is the payoff.
Now that I think of it, the track has a bit of that Mega Man ZX vibe to it (Green Grass Gradation).
Anyway, good work on this remix. Rainbow Road has always been one of my favourite audio tracks from MK64, thank you for putting the time into making this remix!