Odd blue on edges of rear tires?

[Darren]

Have you checked tire temps?

What I think most people do in the beginning is to take alignment recommendations from more experienced and faster drivers, which makes sense in a way.

Since they are faster usually with better prepped cars they can also take advantage of more negative camber.  I think that's probably what is going on for you and you might be better off taking some of the rear camber out for now and when the package of you and the car gets faster you'll end up eventually dialing it back in.