I find TOS about the only watchable Trek show for me these days. I grew up watching it along with TNG, DS9 and Voyager. I gave up on Enterprise during its original run. Never liked any of the new Trek shows from recent years. These days I have watched TOS over and over again along with the 6 movies. I watch the odd TNG episode but find it very boring now and no longer really care much about the crew, DS9 even less so and Voyager even less. I think I would find it impossible to do a TNG, DS9 or Voyager re-watch, just the odd episodes from time to time. However I can go through TOS time and time again, the crew work so well together, I love the 60s feel to the show, the Kirk, Spock and Bones dynamic works so very well. I even got my late partner into the show, we tried TOS, TNG, DS9, Voyager and Enterprise, the only one she liked was TOS.
I should just add that I think 90s Trek is way better than most modern television though find it far less interesting than 60s Trek. I should add I generally really enjoy Sci-fi from the 60s, 70s and 80s. I like the use of real models etc and am not such a fan of CGI.
For 1/6 Trek figures for me it will be TOS, The Cage, Movie Maroons. Wish we could get TOS Klingons and Romulans.