If you liked Longmire, try Yellowstone
Firefly is a western set in space in the future. Fantastic show. Only 1 season though but they did do a follow-up movie. I think this is on Hulu. Just watch it! Don't accidentally pick Firefly Lane
The Expanse was already mentioned but a big thumbs up if you like SciFi
The Wire may be the best crime show I've ever watch. It just got better every season.
If you like The Wire, try Startup. I just finished season 1 and it has been great so far. A couple of really great actors in this one.
Breaking Bad is as good as everyone says. Seasons 3 & 4 were a bit slow but it picked up again in the last seasons.
Game of Thrones is just great all the way around. I know it may not be your genre but you need to give it a couple of episodes. The characters are fantastic but don't get attached. The thing they did in this series that is extremely rare is kill of major characters. Most shows you can watch the first couple of episodes and figure out who the main characters are and figure that they will be around at the end. Not this show. It seems like every time you pick a new favorite character they get whacked in the next episode.
Stranger Things
The OA - this one is iffy for some folks, but I really enjoyed it.
The Boys - this is a superhero show. I don't like any of the superhero movies except the Ironman series. But this one is way different than most and is really great. Definitely worth a try.
The Man in the High Castle
The Vikings
Supernatural - 10+ seasons
Sherlock Holmes - the one with Benedict Cumberbatch