I think the kelvin timeline is great for the sole fact that it is what peaked my interest in trek. I recently just finished watching everything trek and it was because the 09 movie was cool and got me to start watching the different tv series.
I agree that tng 1 and 2 can be difficult too. I think it was just genes Star Trek that I had trouble with. Once he was no longer leading the show it picked up for me.
Not to say that it’s bad or I don’t like it. But compared to the rest of trek that’s what I like the least.
Khan was a great movie and I really enjoyed trek 2, 3, and 4. I think I was burn out by 6 as I’d just finished a ton of trek at that time.
Finished tos season 3, watched all of tas and prod, and then did all the tos movies to finish it off. So after 5 I was not ready to like another tos trek movie.