Hector came off as rather pathetic. I feel like someone who's been through as much as him wouldn't be led on so easily. Having said that I don't hate the situation he's in now, as Lenore was surprisingly fair towards him despite having him by the balls. Hector isn't the protagonist of this story like he was in Curse of Darkness, so he doesn't have to be a badass. I feel this arc was more about the vampires than him anyway.
Alucard's arc was kind of terrible. The sex bit was just too random, in both the reward and betrayal regard. Introducing Sumi and Taka to his life, they come off as sort of protégés to him. The show gives us glances how they are like excited children and Alucard is having fun parenting them. Then at some point they ponder how they want to do something for Alucard, because he's lonely and feeling all sorts of emotions for killing his father. Feels earnest.
They end up with an offer to fuck him. Erm... uh... okay, I guess? Kind of awkward... wait, no, it was just smoke and mirrors, meant to distract Alucard in order to seize and kill him. Wait, what? Why??? Because he didn't introduce them to every last bit of knowledge in his possession in the span of, what, a week? This arc is easily the dumbest of the four this season gave us. Oh well, at least it ended in a satisfying way, Alucard taking no shit and hardening up. Just hope it will be just that and not a catalyst to turn him into the dark side.
Isaac's arc was alright. I like his character (definitely an improvement over the homoerotically flirty redhead in Curse of Darkness) and his interactions with the shopkeeper, the captain and, finally, Miranda. But he's kind of silly with his frustration with the guards. Thinking the situation objectively Isaac should be aware the night creatures are something people would naturally have a problem with. Hatred is very much understandable. Not letting the guards stand in his way is one thing, but him basically judging them bigots is too much. The final battle against the mage guy was cool, but.. kind of separated from the grander scheme. I mean, the people-enslaving mage was just some random dude Isaac engaged only to get bodies for his army (and fanservice tbh). Unless it ties to some grander plot concerning Miranda in the next season...
Saint Germain was something entirely else than his Curse of Darkness incarnation, but I liked it. Overall Trevor's and Syfa's arc was good and filled with intrigue. The Judge didn't need to have his own dark side story, but I'm glad he did. As Lindenfeld is destroyed and its inhabitants killed, the revelation of the Judge as a monster himself is the icing on the cake that paints Trevor's and Syfa's arc an utter failure. All they managed to accomplish was helping Saint Germain enter the infinite corridor, yet it's by no means due to their lack of capability, but more for their carefree attitude towards the evils of the world. I imagine we'll see a much more serious pair in S4.
This season is probably my favourite so far, as I enjoy a character-driven, calmer setting. Castlevania doesn't have to always be about active monster hunting. This season gave us detective work, a journey, politics, and adjustment difficulties to isolation (which kinda failed, but was still worth exploring).