The track looks good, the flow is really nice. Especially the camber and elevation changes make the track very enjoyable.
I have some feedback though. The track is in dire need of some Grass FX which is easy to implement but makes the track a looot prettier. The scuffed concrete barriers on the uneven RTB terrain are also visually unpleasing. These two things would make it a 5 star track.
If you want to really improve your track and bring it to the next level you could think about adding a physical mesh with slight displacements which would give it a laserscanned-like feeling.