How to keep things intresting whilst keeping a simple shape

I need help. I want to make alot of tracks, but the problem is that I don't want to constantly think of different ideas of the skeleton of the course. I want the tracks to drive roughly in an oval shape, but not perfect. But, I've seen just having an oval will probably get your track deleted, so I want to know; how do I keep the skeletion of the course roughly an oval, but still keeping things intresting enough that it's not considered a 'lazy' course and is deleted? Thanks in advance!