It was a cute use of the mechanics, yeah. Though for the most part the core Templar/Assassin thing is fairly arbitrary other than the game wanting to paint the Templars as vaguely worse than the Assassins.
Eleven games in and it still seems mostly determined to paint people as inherently fairly shitty and corrupt and the Templars and Assassins as two sides of a deeply unpleasant and bloody coin, fighting each other mostly because it is in their nature to do so more than for the sake of the broader ideals they hide behind.
Similarly, eleven games in and the explanation for the importance of these various magical artifacts is just that aliens did it, and they were just as garbage as everyone else. 
It’s a very narrow-minded series, with occasional bursts of humanity in the historical tales. I just remembered I played a decent chunk of Unity, too, which I was apparently in a hurry to forget–I would guess it is the series at it’s most Everyone Is Bad as it leans pretty hard into loyalist sympathies to contort the story into its ultimate shape, keep the revolution as much to the sidelines as possible, and have some kind of cooperative animosity between Arno and Elise.
I think what I liked most about the story in Origins is that it’s dismal thematic baggage felt less nihilistic and more personal.
We see two parents spiral away from each other as they grieve in an action hero sort of way. It’s a bit of a weird have-their-cake-and-eat it framing, as the core fun of the game is doing the things that break the characters down and ultimately cause them to disappear into their new professional mantles of mask and blade … but as such bait-and-switch themes in action games go, I felt it was reasonably well performed and portrayed and it’s a real shame the game is so long with so much stuff expanding in the middle of that relatively simple tale.
I think Origins is also the weird Ancient Aliens stuff at its finest, blending Bayek’s religion, the occupation of the greek dynasty, and the supernatural sci-fi together in a way that hits Bayek’s journey head-on in how it pulls at his motivations and insecurities.
It’s not brilliant storytelling, but it’s definitely my favorite of the AC games I’ve played.