Started with a shortlist of about 35 shows. Ultimately (and painfully) got it down to the following. It's some combination of shows I love, shows I respect, shows I think are important, and shows I think are measurably excellent, though the precise ratio of each of these varies by show.
In alphabetical order
Caroline, or Change
Fun Home
Hamilton
Here Lies Love
Natasha, Pierre, and the Great Comet of 1812
Next to Normal
Passing Strange
The Scottsboro Boys
A Strange Loop
Urinetown