My favorite Ross course that I have played is Plainfield CC. It seemed a perfect member's club / course for frequent play. It is definitely a course where I wanted to walk from 18 green straight to the first tee.
Close behind would be Pinehurst #2 (pre-resto), which I am eager to play again...photos of C&C work look incredible.
Holston Hills and Brookside CC are two other outstanding Ross courses that are among my favorite courses by any architect.
Scioto CC, Mountain Ridge and Hyde Park G&CC are 3 others that I really enjoyed playing.
2014 plans include trips to both Minneapolis and Detroit, where I hope to see some more great Ross (big targets are WBYC & Oakland Hills).
My favorite Ross remains Plainfield, with #2 (post-restoration) close behind. I can think of at least 25 Ross courses that I really enjoy and only a handful that I don't.
In rough order: Plainfield, Pinehurst #2, Oakland Hills South, Brookside (Canton), Holston Hills, Roaring Gap, Augusta CC, Mid Pines, Scioto, Pine Needles, Charlotte CC, Mountain Ridge, Carolina GC, Hyde Park, Mimosa Hills, Columbus CC, Southern Pines, Springfield, Sedgefield, Shaker Heights, Myers Park, Ravisloe, Granville, Congress Lake, Broadmoor, Shennecossett, Lu Lu, Grove Park Inn, Camden, Catawba, Miami Valley...
Having moved to NC two years ago, I am trying to see all of the Ross courses in the state (and surrounding areas). Some real sleepers include Ross nines at Fort Mill and Monroe, both just south of Charlotte.