It is all still up for debate since research and testing is always showing us new things, but I do think that R1a was the main source of both the Light eye genes and Blonde hair. Red hair seems to be a mutation which can only affect those who already have the usual light-hair genes (I forgot where I read this, I will try to link it if I find it). The original Paleolithic Europeans though likely already had light skin, but maybe not as light as the R1a.
Thank you, but in all honesty there are many much more informed members on this forum, especially the creator of the forum, Maciamo. I agree with him on most things. My y-haplogroup is I2a, though I myself was never tested, but my father's brother was and his results said that he was I2a (since we share patrilineal ancestry, I must have I2a aswell).
I don't know much about skull measurements and skull-classifications. It is best left to the professionals due to its complex nature. I also am hesitant to use it, because skull-classifications are often used in a biased way.