CTR had much more depth.

CTR also rewarded you for understanding the mechanics more. Some boost pads gave you a boost with a higher top speed (blue flame). If you knew how to maintain a boost, you could maintain that blue-flame boost indefinitely.

It’s just that to do that you had to hit nearly every boost pad, triple boost at nearly every corner, and avoid all the obstacles (including touching walls). It’s hard to maintain it, but even maintaining it for a little bit can really launch you towards the front.