I think the driver of an education / resume ought to be things like styles and uniqueness, whereas states -- specifically, one per state, acts more like a constraint.
Oakhurst in WV, for an understanding of what the play of golf once was like, and how the architectural features of the day related to that play.
Royal New Kent in VA, because it is similar to the architectural mode of desert courses: it redefines what you think can be done with the land. It shows you the "portability" (and limits -- this course is not very walkable!) of design concepts, in this case "Irish links" over Virginia ravines. Also because it ought to teach you not to play by the card but by the land. (If you need the crib note on that: look at slope and rating -- move up one set of tees!)
Speaking of scale: Bethpage Black in NY.
Pinehurst #2 in NC, because: A) you don't have to use length or narrow playing corridors to defend par; B) it is possible to build a course for the enjoyment *and challenge* of all; C) angles still count for something; D) it's a great walk.
Harbour Town in SC, because of similarities and differences in its answers to the questions posed of Pinehurst #2.
I would include a "knockoff" course somewhere in there, because it shows the importance of place, sort of the architectural equivalent of in media res, to design, while at the same time helping you realize the importance of judging the playing characteristics of the hole and not just the views. Also, an "obverse" lesson in routing. So maybe the Ross course at Boyne (MI), Renditions in MD, or Bear's Best in GA.
Shadow Creek in NV, because at the end of the day a golf course is a manmade artifact, no matter what the marketing brochures say -- and the quality of the course is not solely a function of the land but of man's hand.
Sheep Ranch in OR, because even though a course is a manmade artifact, that doesn't mean nature should be ignored, much less fought any more than necessary. (There is such a thing as an architect doing too much!)
Pasatiempo in CA, because everyone ought to know something about Alister MacKenzie, and if you can't or won't travel overseas, and don't have really good connections, this is your best shot!
I wish I could add some examples of sterling routing like Linville or Cascades, but those states are taken. What are good candidates from states not already taken?
Mark