Good suggestions here, I absolutely 120% agree with Justified and came here to suggest that, Hats off to whoever mentioned the shield too.
One that wasn't mentioned which might be to your liking. It doesn't have the crazy fight scenes banshee had but it DOES have the raw emotional power Banshee had
Bron/Broen
http://www.imdb.com/board/11733785/
You know it's good too when both America has remade it, and the UK is remaking it.

Are you watching the new season of Power (on Starz)?

I really enjoyed "JUSTIFIED". Granted, it does not compare to Banshee in the action department, but it does give one 5 seasons of enjoyment.
I'm in my second watching of Banshee right now, and like seeing things come together organically without the waiting. Will probably even give it another watching this winter.

Maybe Strike Back. Ray Donovan is really slow.
Metal forever.

Donovan's not about the action but drama and family dynamics.

Ray donovan is ok, but don't expect epic fight scenes like banshee. The first 2 seasons of strike back has very similar action and fights but after that it goes to crap when they change the actors.

Orphan Black
The Man in the High Castle
Bosch
Legends
Not necessarily full of action and fight scenes but they really held my attention like Banshee.

If you haven't seen Justified, you have to
Justifed is excellent. Some of the best dialogue and characters ever. Much like Deadwood which also featured Timothy Olyphant, even the drunken bums wax eloquently on Justified.

Justified and Banshee will always be 2 of my top rated shows of all time
put The Shield and Lost around that list and we're friends

If you haven't seen Justified, you have to. If you like Banshee, it's pretty much guaranteed that you'll love Justified.
The shows feel like they're written by the same person, both have the same witty writing, brilliant acting and intricate story lines. Very relatable main characters that are heavily flawed, just like Hood or Carrie. Very memorable villains. And so much more.
Justified and Banshee will always be 2 of my top rated shows of all time.

There are 2 shows I'd bundle with Banshee: Spartacus and Daredevil. All are action based and does it really well.
Spartacus has more humor, lots actually, I think it works great. Due to the death of an actor, the 4 seasons are a bit wonky (season 2: "Gods Of The Arena" is actually a prequel to season 1), but watch it in the same sequence they were made for maximum enjoyment. First season is a bit rough, but it feels like every last department were fast learners, it improves into a good looking, well paced show fast. My clear favorite action show till Banshee came around.
http://www.imdb.com/board/11442449/?ref_=nv_sr_1
http://www.imdb.com/board/11758429/?ref_=nv_sr_2
Daredevil is well made, kinda gritty too and low on humor. Even if its a superhero show, I'd say he isn't that much more "super" than most of the Banshee cast. His 2 friends do drag a bit (especially Foggy), but they are my only real issue. Think of Foggy as Daredevils mother, then he becomes comic relief. The villains are great too.
http://www.imdb.com/board/13322312/?ref_=nv_sr_1

Not exactly about their quality, the real problem is the network, they seem to be very tight on how explicit their violence is going to be, and since The Walking Dead lost their hand a long time ago and other shows like Mad Men and Breaking Bad were both VERY slow, I'm afraid of how Preacher will turn out to be.
The first few seasons of BB seemed to CRAWL. But shows being slow isn't always a bad thing. In fact, sometimes it makes them even better and more fleshed out. I'd rather take a high quality show than a fast paced one.
Alas, here is my answer to OP's original question:
The Shield
Sons of Anarchy
LOST
Dexter
Six Feet Under
Deadwood
Fringe
Fiends
Mad Men

I see. While I'm a huge fan of the comic I'm nonetheless prepared for massive changes. The previews and reviews so far has confirmed that much. Not that I expected anything less - there are certain things in the comic I wouldn't expect anyone would dare putting on TV.

Not exactly about their quality, the real problem is the network, they seem to be very tight on how explicit their violence is going to be, and since The Walking Dead lost their hand a long time ago and other shows like Mad Men and Breaking Bad were both VERY slow, I'm afraid of how Preacher will turn out to be.

Only problem with Preacher: AMC
You think they'll be unable to pull off a decent adaptation?

i LOVE Luther.
Luther and Alice Morgan!
Idris for James Bond!
Remember us, for we too have lived, loved and laughed

How about going back to old shows? Sometime it's better to go back and see what we have missed?
Look into these shows
Justified
Luther
Bosch ( gets better after few episodes and season 3 will be coming soon)

Only problem with Preacher: AMC

Preacher
.
It was the supposed similarities to the comic that got me into Banshee in the first place, and only two days after said show concludes comes the TV-adaptation of Preacher! Begins tomorrow.

I'd give Justified a run for it's money, The Shield too, Bloodline, Rectify and Kingdom are also criminally underrated

of course it's still going.
Oh, the humanity

I disagree. I felt VERY let down by Ray Donovan, and had no interest in the second season. It's still going?

I would've bet money that those shows would be mentioned. They always are.

Yeah right down and it's one of the finest TV shows to ever have been made right up there with Banshee The Sopranos the wire and Breaking Bad