Oh and re-reading this thread a bit.... My Top 10 in no particular order:
Breaking Bad - Best show I've ever watched. I think Boone said it takes a few shows to get into, but once you're in...phew! Ever episode and every season seems to just ratchet up the tension as you watch the journey Walter and Jessie go on. The last season was some of the most tense TV I think I've ever watched!
Friday Night Lights - Needs no explanation in this forum I'd wager. Kyle Chandler will always be Coach Taylor to me, and as much as my wife makes me watch Nashville and insists Raina Jaymes belongs with Deacon, Connie Britton will always be Tami Taylor, Coaches wife.
Battlestar Galactica - I like my Sci Fi hard, and this show was so good. It's a million light years away from the original show and the Cylon mystery keeps you guessing. It's also a very interesting study on faith and religion. Loved it.
The Expanse - I mentioned it above, and this is more Sci-Fi fantasy I guess, but based on very real physics. Love this show.
Preacher - On Amazon Prime over here, but loved the first couple of series. I was a big fan of the graphic novels so this was a treat for me. The premise is that he's a small town preacher with a shady past and is gifted with the 'word of God' which means he has the power to tell people what to do and they do it. It's darkly comic.
The Good Place - On Netflix. It's a short 20 min show, just finished it's second season. The basic premise is that Kristen Bell plays a woman called Eleanor who wakes up after dying to be told by Ted Danson that she is now in Heaven, or the Good Place. However she's there by accident because she was actually a bad person and should have been sent to the Bad Place. I'll not spoil the twists and turns for those who haven't seen it, but it's a show that's much deeper that a simple 20 min sitcom.
Game of Thrones - Not gonna say much about this. Love it and I'm guessing most of you may be already on board for the ride.
Wynona Earp - I'd class this under my own guilty pleasure. But I also love Supernatural so this feels like a natural bedfellow. I also think I may be slightly smitten with the lead character! LOL It's got a good deal of humour in it too. The basic premise is she is the great granddaughter of the famous Wyatt Earp and she inherits his gun 'Peacemaker' which is capable of sending demons back to hell. Kooky premise, but I really enjoyed it.
Westworld - Way better than the original film it's based on. This show hooked me in with the mystery. I figured out some of it before the reveal, but I'm so ready for season 2!!!
Alias - I'm still a big fan of the spy series, though it loses it's way a bit in the later seasons.
Being Human - What happens when a Vampire, a Werewolf and a Ghost live together. The UK series is better than the US one so watch that if you can get it.
Honorable Mentions: Farscape (my guilty pleasure), Life on Mars (the UK version not the US one), Mad Men (mentioned by others), Sherlock (the UK series with Benedict Cumberbatch in it), Veronica Mars (another guilty pleasure) and the UK TV show 'Teachers' where you'll see a young Andrew Lincoln way before he was Rick Grimes.
By the way, The Wire is on my 'to watch' list but I'm glad I'm hearing good things about it.