Hi Demonboy
I was hoping you would ask this question !!
I agree that it is a very pretty coin !! and for sure nothing to be ashamed of,, PCGS has done you a favor by slabbing this coin as a 65 though.
My reasoning is one of experiance with this coin series,, but I will use the PCGS grading guide to simplify the process.
PCGS grading guide says this about an MS-65 coin,,Minor marks though NONE in the focal areas, the coin will have an above average strike.
Now that little nick is not a big deal and the coin could possibly grade as a 65 with it alone, but !!!! combine that with the strike on the coin,, we can use the reverse since it is the most notable strike problem for this particular coin,, look at the center of the facses sticks.. Ignoreing the center bands,, look at the center stick, do you see the flatness on this stick and some even spreading both east and west especially just below the center bands? that is a weakness in the strike of this coin, the obverse has similar weakness although not as noticeable but the curls on the forehead, and the lower wing feathers.
Now this is what PCGS says for an MS-63,, Moderate number/size marks/hairlines and the strike may not be full.
Thus my determination of an MS-63 for this coin.
Hope this helps you to understand,, it really is not that uncommon to find disagreement with grades of slabbed coins even those of the top tier companies,, and it is no way a push at you personally!!
Check out the reverse of this 1917, it is also a 63 but for reasons other than strike problems.

Rick