General observations: the lab beneath the faux Fords' house is the room where we see Bernard talking to Dolores about dreams and being free while she is clothed - glass walls inside concrete walls, unlike anywhere else in the compound which is all glass, lending credence to the idea that Bernard is indeed a android version of Arnold and it is Arnold who was speaking to Dolores early on, giving her Alice in Wonderland, etc. Especially since Bernard can't even see the door and seems to have never been in that room before.
I don't see where it makes much difference whether Dolores is robotic or organic, but Stubbs does say in Ep. 1 that she has been rebuilt so many times she's practically new.
I suspect Charlotte, the executive director of the Board, is an android. Ford makes a point of telling Theresa that within Westworld, he "made ALL of it" and we've only seen her in Westworld. He also repeats her phrase "a blood sacrifice". Interestingly, Charlotte says, "The gods require a blood sacrifice." while Ford says "The situation requires a blood sacrifice." in the middle of his I have a huge honking God-complex speech, leading me to believe she's programmed. I'm guessing Charlotte crossed him at some point earlier and he killed her and made an android version to do his bidding - as he is going to do with Theresa. The body being constructed in the lab will likely become Theresa.
I'm all about William = Man in Black. I read a theory a couple of weeks ago that William falls hard for Dolores (which did indeed unfold in this week's episode) and in her quest for the maze and sentience, she will end up rejecting him (or she will lose her shot at the maze and never reach full sentience, which he will feel as a betrayal by the park itself), and this will be the penultimate blow that turns him, within the park, into full-on black hat. This would also explain his interest in the maze and Dolores, and why he both regrets that "after all we've been through you still don't remember me" and yet treats her so horribly.