Totem Warrior 20
College of Valor 20
Life Domain 20
Circle of the Moon 19
Battle Master 21 - I'm sure people will disagree, but I think Battle Master is the most Iconically 5e subclass. It does something that isn't modeled in previous editions.
Eldritch Knight 20
Shadow 20
Oath of the Ancients 18
Hunter 20
Arcane Trickster 21
Scout 20
Shadow Magic 20
The Celestial 21
Illusion 16 - Seriously, how the eff is Illusionist more ICONIC than Sparky Sparky Boom Man Evoker?