High quality synthetic pants, shorts and jackets at Goodwill??
Yep. Gore-tex, Dry Plus, wool, wool-blend, etc. Sitka, maybe not. You don't need to go to the top of the market for good synthetics. Those brands may indeed be worth the price, but that did not seem to be the question from the OP.
Regarding performance underwear, I have a pair of $20 Underarmor boxers that are 10 years old, and 4 $20 pairs that are 3 years old. The older pair are twice as good quality as the newer pairs for the same coin. I'll look elsewhere for boxers next time.
