Hole 6 at The Whippin' Post, Paw Paw: 874 foot par 4 over a wide rolling fairway with forest on the right. Hole 13 on the Woodshed is a beauty too, 556 foot par 4 that takes off across the field, then over the dropoff down to the treeline, and back up a hill to the basket. (There's actually 4 or 5 of my new favorite holes there, but I really enjoyed these two. I didn't enjoy The Gauntlet so much as survived it, most grateful 5 I've ever gotten.)
Hole 27 at DeLaveaga is definitely one of the most picturesque, giving you a view out over Santa Cruz all the way to the ocean, and pretty fun to throw way out into space. But I think I like Hole 17 there better, the fairway makes a big arc to the right on a hillside that slopes down left to right, with the tree canopy coming from the trees on the right, and a whole bunch of trees down the slope to the left. I don't know why that one's my favorite (actually, hole 8a's where I got my only ace to date), but there's something about the shape of it that just gets me. Hole 13 there's pretty awesome too. Hell, that whole course is a delight.
Codorus State Park in Hanover, PA has several that would be signature holes anywhere else. I'll have to play it again to find the ones that give the extra thrill, hard to sort through all 54 of 'em after only 1 weekend.
Coyote Pointe DGC at Lake Casitas's most scenic hole is definitely 16, it's own "Top of the World" shot that goes 520ish feet out, but a couple hundred down, and provides an impressive view of the lake. But it's hole 15 there (in the long position, under the enormous oak on the hill) that I always get psyched up for.
I've only played Brandywine once, so my opinion might change on this one, but I really enjoyed hole 3. Hole 4 is "The Beauty", a big downhill shot over a creek to the basket, but hole 3's topography is really interesting, with the fairway dipping and coming back up, and the basket on the high side fo a 5 footish stone wall that runs along the road. Great hole.
