I just bought a 15" retina today and noticed the eye strain as well. That's how I came across this topic. I went in to display in settings and color and did a calibrate. I change the gamma from 2.2 to 1.8 and will see if this will help. Why don't you try that out and let me know if it works for you. Makes the contrast a little brighter so it may help.
Let me know.