I'm happy the series is back, and overall I enjoyed the episode. I actually liked that it was obvious that Kyle was a hallucination and not yet another timetraveller version right from the start, because of how he never did any physical interactions like subduing the guard or keeping watch on the doctor. Bringing Kyle back would run counter to so much of the premise, that I liked that it was clear that that wasn't what they were doing. And knowing that I quite enjoyed him cheerleading Sarah.
But seriously, Ellison needs a more competent plan to teach John Henry. I'm no biologist, but I'm sure it is not that hard to answer why animals don't have ball joints for elbows and knees. My knowledge of skeletal mechanics is vague, but I'm fairly sure that it has to do with stability (like how shoulders can pop out of joint and such), and efficiency of movement and so on, and that John Henry should be able to find a detailed answer to why that "design" evolved even by himself.
Also, see the "evolved" part, once he was allowed to google he should have had his answer to the how part (many many generations of organisms with mutation and natural selection, over a lot of time with lots of trial and error and died out species and so on and so forth) and his question wouldn't be about god and the number ball joints in mammals anyway, unless he was actively mocking Ellison. But terminators never really seem all that good at sarcasm, so while I hope he was mocking his inept teachers trying to give him obviously insufficient and inconsistent explanations, I don't think that's what happening.
Anyway, even if they for some bizarre reason think a terminator would be more ethical if it believed in creationism (though the mind boggles at that) they could at least answer with the physics of skeletons, or John Henry will walk away from these lessons with the basic idea that terminators aren't just physically superior, (though are metal joints even all that great over the long term compared to the organic solutions?) but that humans are too stupid to live and deserve to die out or something.
I'm also not sure it's a great idea to give the thing you want to prevent from becoming a killing machine war toys of weaponized machines that are more or less mini-terminators. Then again Weaver is a terminator after all so who knows into which direction she really wants to coach him. But I liked that John Henry found out about Weaver not being human.
I liked the doctor and how Sarah edited her story to connect with her though. That was sneaky and very efficient to exploit her domestic violence history and sympathy. Admittedly it's a bit of a cliche, otoh considering the statistics not unlikely either. I liked the twist that the cop Alvin we started out sympathetic to turned out to have been the one to hurt her in the past.