Hi there, I'm a backer and have only played very few rounds due to a lack of time and friends over to play with.

All in all: Thanks, mate, this will go a long way. It reminds me of the fun I had with Mario Kart, but since I recently tried that old goat a few months ago, I'm very grateful for the more modern controls and physics that immediately work.

As a quick first critical remark: A lot of the tracks, especially in the 2nd cup, are hard to read if you're new to them. This may be on purpose, since I'm sure it will get better once I know the tracks, but it could also be a case of you as the dev knowing the tracks by heart. If you tried to make the tracks easily accessible, I'd like to point out that this didn't work out on all tracks. Knowing where to turn was sometimes really hard to see, additional markers on the track or the sidelines would go a long way of helping out.

If this is something you'd like to look into, I'll gladly post more precise descriptions and tracks names.
Of course, only if this complaint is something more people have, maybe it's just me.

Cheerio!