That one clansman in the beginning that dies, seems to consider taking care of The Sword much too serious, posing the possibility that he is very envious of Kazamatsuri for that chance... instead of him. His overreaction at the sight of Kazamatsuri looking at The Sword also indicate that his attempts to kill was just so he could be a hero for the clan and get to take care of The Sword instead.
Mizoguchi keeps Heishiro around specifically so he would develop feelings for Koharu. Indeed, it is a long journey back for Heishiro but he could of probably done it with some supplies and some help, especially since Mizoguchi had sent Suzuki away claiming how dangerous it might be to stay. Why not make one stay until the other gets better and send them both packing?
Kazamatsuri is not Ambiguously Gay, just confused and without a proper role model, wondering around unsure of what to do, wishing the heavens to help him — an interpretation that is partially proposed by actor/singer Hotei in his song for the film: "Save Me".
Lady Okatsu's death happens off-screen, yet the last we see of her alive is having been restrained by Kazamatsuri in a hand hold — it is possible that he simply let her go but she persisted in attacking him and gave him no choice. Her scream that alerts her men starts out strong and sure and ends broken, possibly indicating that she was stabbed by Kazamatsuri just as it was happening.
Everyone Is Jesus in Purgatory: The eastern philosophical kind, as in: Everyone was Siddhartha in a Past Life — if Heishiro's acknowledgement of the 300 years since the story's setting is meant to be more than just a joke.
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