The templar at the intro cutscene looks a lot like Uther from the Warcraft universe, and I think that might be intentional considering ex-Diablo devs worked on this game. Also, I think Civvie 11 would snap even more if he covered this game considering the amount of sewer levels and that a lot of the levels are copied and pasted, so it gets a little confusing...
I have a theory of why the game became such a chore for you: I think that despite this game giving you the choice to play it in singleplayer they never balanced it around that, unlike Diablo, Borderlands, or any other game like it where the enemies only get "beefier" depending of the number of players in the session. And if it's true, I don't know if it was out of pure laziness, lack of time because the publisher was pressing the devs to release it sooner, or if they did that on purpose to force more than one people in a group of friends to buy the game. (and since EA is the publisher, I think the latter is the most plausible)
And speaking of multiplayer, based on what you showed, this game gives me huge The Division vibes. It has the same logic: You can play it alone, but it's only fun when you are playing and messing around with friends, and the dialogue, plot, and characters are incredibly generic. Well, at least Hellgate: London has demons, not generic human baddies that somehow survive many bullets.