1) It's the subject of ヒ?ォ窶堋ュ窶堙遺?堙ゥ. 窶ーツス窶堋ェヒ?ォ窶堋ュ窶堙遺?堙ゥ窶堙個?ナ?P窶堋ェツ。
2) Yeah, it's just with a lengthened final vowel. It makes the utterance more emotional (in this instance at least), like something important is following. At least that's my feeling. Someone else could probably give a better explanation.
3) Yes, you are correct.
4) Yeah, it's typically a male sentence-final particle, similar to 窶堙ヲ, but I believe devoid of the opinion-giving aspect. Of course, women can use it too, but it's less common, and generally reserved for motivating themselves or others, I think. Again, probably more there that I'm missing/forgetting.
5) It shows a change of state from not needing to wrap a sock around the throat to needing to wrap a sock around the throat. So it was fine not to do it a little while ago, but now we need to.
6) Yes. It's like the "time" in "it's about that time" or "around this time..."
7) Yeah, but not as "whether A or B," as "when it comes to things like A and B..." X窶堙俄?堋ゥ窶堋ッ窶堙??堙 is a set expression to show that a person is ahead of the curve at X, or that something is outstanding/extraordinary when it comes to X and things like that.
8) I don't know what to say about this one. I feel like I'd have to read the story to get an idea.