A few more:
11 at Merion (definitively the most mentally difficult)
8 at Pine Valley (perhaps the most penal, if missed)
17 at Oakmont (you are seriously worn down by this point)
10th at Royal Melbourne West (probably the most deceptive)
3rd at Kingston Heath (enough to give you fear of the beach)
11 at Quaker Ridge (perpetual thief of good rounds)
The Dell at Lahinch (go ahead, find the farmer)
And with a twist:
The 2nd shots at Royal Dornoch's #2 and Shinnecock's #11 .....because, if you miss these greens on your 1st pass, you are seriously praying for par