Rock Rock Mountain (or Alpine Pass in PAL for some reason) is one of my favorite tracks in 7. There is a large portion of gliding in this level, so it was enjoyable to play if you wanted to try the game's new features. The aesthetic reminds me of World 6 from New Super Mario Bros Wii, and I think it worked really well.
Daisy Hills is also just a pleasant track to race on. It's not particularly difficult, and the scenery is really beautiful. I just wonder if this is supposed to be an area in Sarasaland, which I would really like to see developed further.