I have a few general settings for various situations but they get used for things I want to quick and dirty. My 5DII/III and 7D have profiles I have built over time. I have settings I built for using a flash, various lighting types, macro work, different effects (I built instagram filters since everyone and their bride loves them) etc. One thing all my LR presets include is Lens Correction and CA. All in all you kind of learn them as you go and need them for specific situations and desired effects.
I also follow up with some work in PS on most images as well for various filters and effects that LR can not do.