Minor Spoiler alert!!
Good questions..I think Rust's vision was partly drugs, partly fear-adreneline induced and also in a sense, a cosmic destiny or this moment is what his significance is" symbolically.
Unresolved for me:
I swore that Marty's daughter, who had the sexual drawings and reenactments with her barbies early on was going to be tied to some exposure to the Yellow King or his cult somehow. Since he worked at the schools.
Marty also said In his interviews that the evidence was right in front of him..calling it the detective's curse. I guess the whole point of that was to show he was not at home and his girl was crying for his attention.
Yeah the whole Marty's family possible story never showed up.
Fine by me. Last episode was great