what I like of Days Gone's characterisation:
I like that Deacon is a character that genuinely struggles with his ludonarrative disonnance in a way that affects himself and other people.
When he's alone, he's ansty, unhinged and bloodthirsty. He has zero remorse in murdering his enemies. When he's with others, he's "normal", well - as normal as most people can be.
But later in the climax of the second act, we see Deacon's bloodthirsty side spill out once it was revealed that Carlos was an old friend of his, and he has zero qualms going off to commit mass murder of hundreds of Rippers, and that action of his - which he has zero regret or remorse for - makes other people very uncomfortable of him in that moment.
And throughout the game - we see this reflected in smaller ways. He's constantly dishonest with Boozer about his lingering motives to move on from Sarah, Boozer constantly calls out how Deacon is regularly a daredevil who jumps head first into situations that is likely to get him killed.
From there, we can see now - Deacon's continuous struggles, why he finds it difficult to plant his roots, why he has difficulty being honest about his problems. He lives his life, as if wanting to burn out - because he has nothing to live for. His best friend grounds him to a semblance of reality, but if not for Boozer, Deacon would literally be a crazyman.
And that is not a part of him that other people were able to touch or affect directly. Boozer can see it, and call him out on it when he sees how he acts when talking about Sarah, but it's not like Deacon becomes any different.
And once the game has you reunited with Sarah, that becomes even more pronounced. Deacon has been living in some sort of delusion-land, reminiscing of Sarah non-stop. But seeing Sarah, hardened by the militia life - made him really uncomfortable. He has difficulty coming terms with it.
When Sarah was able to mercilessly kill another human in front of him, he was shell-shocked. His wife has become a different person, but at the same time it's still his wife at his core, and learning that her plan was to save the Freakers instead of kill them, while abrupt, brought a different meaning for him.
And while I don't think it was the best execution there - I feel like that was a strong impetus for Deacon to suddenly look inside himself, and want to change. To have something to live for.
Ultimately, I think Deacon was a really strong character. It's not the best execution - I feel like his outlaw MC aspect wasn't really as highlighted as strongly as it could be, I feel like his shift from becoming a somewhat selfish, unhinged person but good at heart person to his more paragon-ish side at the final arc wasn't the smoothest transition feasible, and I would've liked more interactions with Captain Kouri/Doctor/etc etc for him to find more of his humanity within Camp 4/5...
But damn, I'm pretty impressed overall. And he's not the only well-written character in the game. Iron Mike, Captain Kouri, Skizzo, Addy, Rikki, O'brian, etc. It had a really strong cast and had their arcs been tighter and less bogged down by a lot of missions that spread out their character arcs too loosely, their portrayal would be recognised more.