These maps are overall pretty good, with simplistic layouts and clean visuals! Sadly, I do have plenty of gripes with some of the maps.
Kart Krew Horizon is... a strange name for an actually really fun course. It's simple and I like the transitions in and out of the stormy areas. The bridge sounds are a cool touch! Perhaps a more suitable name would be simply be "Stormy Horizon", however?
Twilight Mansion is a pretty fun Ghost Valley-esque level! I liked the section going into the well and I liked the exterior visuals. Though, the merge in the mansion itself after the waving carpet section can lead you with a blind turn, and the visuals are actually rather lacking here. I'd have loved to see more love put inside the castle and well!
SIK Dragon Valley is cool to see, I really liked Super Indie Kart before learning about SRB2K! It's very faithful to the original layout, maybe a bit too faithful. The spikes placed right after a turn on the right is a bit tough to get by at high speeds- especially so in Hard mode, and Hunter Snake can really screw with runs of this course. I still rather like it out of nostalgia though!
Polar Paradise is probably my favorite out of these maps save for Horizon! The layout is fair and I like the spring placement near the end that can be risky to drift for, and the simple visuals lets the thick snowfall shine. The Penguinators are also a cute, fair hazard and I think we could have seen them more, maybe on the sidelines watching! I think a better music credit is order though. Who's Mega Drive music is this, where is it from?
And Scorch Desert, I'm sorry. I like the layout, I like the textures but *god damn* that heat haze is way too powerful for me. Having the whole screen wave so intensely through the whole course is way too hard on my eyes. I got a single lap in Time Trial before I had to call it.
A pretty great and significant revamp of a map pack that already had some memorable tracks like "SIK Dragon Valley","Polar Paradise" (formerly Arctic Lagoon), and others.
Previous versions of your maps had wild jumps which was chaotic in multiplayer, so these revisions are nice in scaling them back. I'm kind of iffy of the off-road before the boosts on "Polar Paradise" as it slows the flow of the track. The Penguinators are a fun addition.
"Twilight Mansion" being another revision looks better. I think it might be a bit too dark in the beginning area, so some caution is needed when items are here.
"Scorch Desert" is a highlight of new material in this update. My main criticism is the final shortcut being an overpowered clutch in the final stretch, especially on the final lap.
As I've discussed in the thread, I hope to see Sonic Colors' "Sweet Mountain", "Joker City", and "Chimera Tower" to make a return in the near future.