I personally love the challenge of the extreme tracks, and as there are only 3 new extreme you can hardly accuse the makers of only catering for people who like the extreme tracks!! There are a lot more levels with lower difficulties.
So what if the cheevs are hard, I love the game as others do, the cheevs don't matter. I'll probably never get the marathon cheev as I always make a silly mistake but hey I don't go online to bitch about it! Just enjoy the game or don't play it.