Patrick:
For me, at least, quirk is not something I add to a golf course ... it's something I find out there that I will either incorporate, steer around, or whittle away at, depending on my mood. The personality of the client and the intended market are certainly factors in those decisions.
Over time, I would say that I have tailored courses to my clients' tastes more and more over the years. My first few years in the business, I thought that good design was bulletproof, and I ought to make the same decision everywhere. Eventually, I realized that if I didn't want to follow Seth Raynor and keep repeating myself, I would have to let my clients (and my associates) factor into the decisions a bit more often. Plus, somewhere along the way, I realized that if the client didn't like a particular hole, it wasn't likely to last, anyway. The original 14th green at Sebonack was a favorite of mine, but I would not have grassed it if the client had spoken up at the time and said he didn't really like it ... because it was inevitable that he would change it later on.
Every client is different. Mr. Keiser is not adverse to quirk in his courses, and his retail golfers don't seem to be, either; but Mike does not like big internal contours within the greens, so we worked on smaller greens with big features at the edges for Pacific Dunes. [It's a wonder that the same client let us build Old Macdonald, but perhaps he understood the need for variety there.] I didn't actually design Bandon Dunes, so I will take the Fifth on what I would have done differently there.
I am not in favor of "dumbing down" a public course to pander to an assumed demographic. All you'd have to do is go see Common Ground to figure that out. At the same time, I now tend to save my more complicated greens for the private courses, on the grounds that the members would appreciate day-to-day variety in the set-up, while the resort golfer is less likely to stick around long enough to learn all of the different hole locations. I can't imagine that the greens at Lost Dunes or Ballyneal would go over as well if most of the players were first-timers. [Even if some people fall in love with those greens at first sight, remember, they are usually playing with a member who's telling them what to do on every tee.]
I have always said that the one element I would tend to save for private courses was blind shots. [I suspect you'd find me telling Ran something like that in response to a similar question in one of his interviews.] But, the only course where I've used more than one blind shot was at Old Macdonald, so go figure!