For the past 3 years, Davi's YADA YADA YELLA has been my favorite VL bloomer. When it starts blooming it overshadows everything in the garden, daylilies and non-daylilies alike. Her WORKING OVERTIME also puts on quite a show and is a massive plant. And PAINTED GIRLS has the best color of any late bloomer that I know of.
Curt Hanson also has LOTS of late bloomers. I tend to find that a lot of his intros that are registered as ML bloomers actually bloom in the L to VL season in my garden.
Mid-late, late and very late bloomers are my favorites!