Agreed.
For me -
Season 1 - Awesome. Very new and fresh with great characters and wonderful tone
Agreed. Not much else to add.
Season 2 - My personal favorite. It carried on everything great from Season 1 and developed it. The show could have finished here.
I liked the Doakes subplot, but didn't care for Lila (or whoever the British chick was). And really, this was them blowing their wad too soon. This should have been the final season. Unlike 1 and 4, this season never cries out to be rewatched.
Season 3 - 3rd seasons are always difficult but this one fell flat for me. I thought it was quite dull and felt extremely different.
I must be the only person who liked season 3. I loved Miguel as kind of a corrupt civil servant villain who destroys people through city-hall instead of the typical serial killer. Their rooftop confrontation is still something I watch regularly on YouTube. The Skinner subplot felt tacked on and could have been dropped though. Not as good as 1 and 4, but all in all, much better than any of Dexter's last few seasons.
Season 4 - Much better than 3 but still suffered from many issues. Lithgow papered over a lot of the cracks IMO and the season isn't as good on a rewatch but still quite strong.
Technically not as good as season 1, but my favorite season because of Lithgow's creepy performance as Trinity Killer. No other portrayal of a serial killer in this show's history seemed as authentic as this one. And so many classic scenes, like Thanksgiving dinner with Trinity's messed up family, Trinity going to Miami Metro and confronting Dexter and of course, the final scene with Rita and the baby.
Maybe it's not fair of me to say, since I haven't been able to sit through all of the later seasons, but I thought season 4 was the last time Dexter was truly good as a show.
Season 5 - I really liked this season. infact I'd put it in the top 3. The only issue for me was the end.
This was the last whole season I watched and the one that kinda turned me off Dexter. I can't even remember why I hated it so much, because it was pretty forgettable, but there were some really stupid scenes. I vaguely recall one in particular where Dexter almost gets caught at a waterfront warehouse by Miami Metro, but talks his way out of some situation with an asinine reason that no detective would ever buy. Wish I could remember the details. Unlike some, I didn't think Lumen was that bad. The writing in general was just bleh.
Season 6 - This was decent. I quite enjoyed the whole apocalyptic angle even though it got incredibly stupid at times. I thought it was a bit of a dip but still fine
Hated it. Watched three or four episodes and then stopped.
Season 7 - This was reallllly good IMO. It tackled the many plot strands well and built and built. It seemed thought out and I was really excited to hear this was essentially part 1 to a 2 season arc.
Watched one or two episodes, which isn't enough to make a judgement. I heard it's better than 6 and 8, but still not as good as the early seasons.
Basically IMO all of the seasons have had redeeming qualities. Some were weak but I honestly believe I could comfortably rewatch all the seasons other than maybe 3. So I hurts to say that Season 8 IMO is godawful. I just can't find anything I like about it. Characters - All pretty much unlike their characters. Plot - Muddled from beginning to end with not one particular strand. Villain - Had potential if he wasn't brought in so late. Pace - What pace? It's been so boring. Writing - Just BAD I may flip out if I hear Dexter say he's "changed" again.
I've watched three full episodes and bits and pieces of other episodes from this season. I couldn't take any more. Whenever Harrison or Hannah is onscreen I feel like Alex in A Clockwork Orange suffering through it. The writing is atrocious. Season 3 is a masterpiece compared to the dreck I saw. I've said it before, but it's a damn shame what Dexter has become. Shows have declined before, but I've never seen a drop in quality this big. It's like they hired a bunch of new sucky writers or the old writers stopped giving a crap.