If I'm understanding what you want correctly, using a segment that is "Visits where Page equals (Distinct Count) 1" should do what you want.  In other words, Count Distinct should definitely work for pages.

I understand how row-based percentiles would be useful.  And being able to see the standard deviation could also be useful, but how would you use t-test?  What would you be testing?

This isn't currently possible, but there is an open idea, so you should vote for that (if you haven't already).