the finale would have been better imo if Rust had passed - they probably could have worked the "forgiving himself" part into it just as well too - but thought the way they ended it was fitting too with lots of questions and "bad guys" left be.
Have heard a lot of complaints from friends/colleagues regarding a lack of explanation as to what the motivation behind all the sacrifices was, etc but I think that was well worked into the plot as it developed as opposed have a full on review at the end. Reading up on Chambers' "The King in Yellow" may make following and making sense out of the series a bit easier, I guess. Same goes for familiarity with some of the socio-economic peculiarities of Lousiana and the US south.
All in all, for me this was the best series I have seen, as in ever (and yes, guys, I did have the patience to watch some episodes of "Arrow" and "Sherlock")

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I knew, or at least very, very strongly suspected, who the killer was at the end of ep. 3, which kind of took some of the suspense away but the series was well worth watching just for the dialogue and the cinematography alone.
Season 1 certainly raised the bar big time for the rest of the show. Hope they keep the same director for season 2 otherwise there is a real chance the gap in quality to end up being a bit too wide.