I thought this was the best written episode in a long time. If you watch it again, every single scene is loaded with subtext, and additionally... many, many things are set up.
It's very easy to write over the top, but it's very hard to write subtle scenes that are both psychological, dense, and emotional. Not to mention, this episode was basically carried by just two people, a feat in itself.
Lennie James is one of the best actors in the biz, and it's not just in the moments of strife that really demonstrate his talent... it's in the small fluctuations of emotions that even the most skilled actors can barely pull off. Watch for it. It's remarkable. A successful actor once told me to not just study an actor in a scene in which they are overly dynamic and emotional... look for their skill in how they handle the quiet moments, the thoughtful moments. This episode was a master class in that.
But this episode was a brilliant way to shake up the emotional arc of the series. Rick's about to reach the tipping point of his primal/animalistic nature... and you need this backstory of Morgan to pull it back and provide counterpoint. This difference of philosophy between Rick and Morgan is going to define the season... and to a large extent, it already kind of defines the comics. Is surviving at all costs worth sacrificing our humanity? Without this episode, we're left wondering why the hell wouldn't Morgan kill those people!!! And that's almost reflective of what the show is trying to get across... that our very own bloodlust and protection of these 'characters' as an audience wants to see them survive at all costs. But, Morgan's backstory delicately places a wrench in that thought process, and for the rest of the season, his philosophy will be pulling on our innate good nature.
The other very big scene was in how Eastman mentioned the difference in criminality. There are people that became killers in this world as a result of everything that happened (like the Wolves, the Governor, even Terminus)... but psychopaths are a different breed. We haven't run into the type that is a Crighton Dallas Wilton yet. But it's a matter of time... and it'll likely be the greatest adversary they face. Plot's about to get good. But this episode was needed to get there.