Last season's finale cliffhanger brought the highest ratings ever to the show's season premiere. Not wrapping all of this up by the end of the season would not be suicide.
Neegan is awesome. I love every minute the dude is on screen. This isn't an "experiment." Neegan is what the tyranny of evil men looks like. How do you think order is brought from chaos?
I'm guessing there just aren't enough machetes to zombie heads for you? Go to the movies if you think this stuff is "slow." The movies these days don't bother with being about anything or taking their time and filling in the gaps. They just careen from action scene to action scene to action scene. The plot providing barely enough motivation for that and falling apart even under cursory examination. Mostly I guess they're action scenes since nothing is ever held in frame and there is a cut every .75 seconds.
The only corner visible here is your lack of imagination.
On the one hand everyone seems fed up with the old style of episodic television where everything is reset at the end of the episode and there aren't really any continuing threads yet I keep hearing about how Walking Dead doesn't wrap up every dangling thread by the end of the week.
What's the longest you've gone without checking your phone? (While awake.)