Yeah it was very annoying and frustrating with all the many finely set up mysteries that meant nada in the end.Your grading is fair @Mrs Smoker, but the hype was insane at the end of season 2, I didn't think it could be topped as a TV show ever at that point, so mine would be higher. I think half the fun of the show, when it was live, was all the wacky fan theories (I preferred most of them to what actually was going on) and break downs after each episode.
Although I loved the show at the time, not sure I could stand a rewatch now, it'd hurt my rose-tinted memories, as it really could have benefited from the more modern 6-13 episode structure of "quality shows" that we see today. The writers where literally making shit up, on the fly, so a lot of it was pulled taffy filler to get to 22 episodes, mystery for the sake of it, plots that went nowhere. Like Nicky and Paulo, which they admitted was a test to see if they could get away with and just plain old unanswered story threads, compared to something more clearly plotted like Westworld. However, it was an important cultural stepping stone to get to where we are now, it wasn't solely responsible but it was certainly at the start of that wave of movie level budget tv shows.
One thing that always bothers everyone is the ending, I'm almost certain that they spiked the original ending because people "figured it out" fairly early on and they pushed it off to figure out later until they couldn't, they only finished writing the final episode very close to the air date. Pretty sure it was around a month before it aired, by which time they'd altered the narrative from "Every question will be answered" to "Emotionally satisfying" which to me it was. Steven King has dogshit endings to most of his books to, because endings aren't as fun as the journey.
Good post by the way.