I can see how the Trio would annoy people to some extent (Andrew especially, dear god what an obnoxious character, I'm not looking forward to seeing more of him). Although having finished up the season now, I ended up being much less bother by the way Warren died than I expected - because it was pretty quick, and because he really was too stupid and unlikeable to live at the end.
I actually agree with you almost entirely, Kestrel. I don't have a problem with season 6 - in fact it was the first season of the show that I bought on DVD. I will grant that perhaps the episodes are a little too one-note - too much misery and angst all at once, rather than ups-and-downs of angst then comedy then action then back to angst, but all in all I think it was a valid direction for the story and the characters to take, it was done well.
Yeah, I can see this, that it's a bit too much, too heavy. I wouldn't want the entire show to be like this, I'd be drowning, but for one season it works.
Joss always said the theme of the season was "Oh, grow up!" The characters are forced to face real life and become adults. Real life is the Big Bad. But the Trio refuse to do the hard work of growing up, of facing real life as it actually is and going through the process. They try to side-step the process altogether, using their powers as a short cut to becoming successful or rich or getting the girls. And that refusal to do the hard work of growing up leads to disaster. (Willow, by the way, does basically the same thing by turning to magic to solve all her problems, which is why she is also a villain by the end of the season.)
I don't think it's any coincidence that after vampires and demons and cyborgs and hellgods, it's a bunch of human nerds that cause the most damage to the Scoobies. Again, it's all about the theme of "real life" - facing the horrors that humans can do to each other. Buffy can't fight them in the same way she can vampires and demons - it's always been a part of the show's and the character's morality that she can't kill humans. The human world has its own laws for dealing with them, and she's supposed to only deal with supernatural threats. But in this show about magic and monsters, it's one human shooting another human with a gun (a very human weapon) that is the big turning point of the season, and that's absolutely deliberate.
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Agreed overall with this analysis, yup. Though, Adam as a thematically appropriate foe, really? I don't have anything especially against Adam, but he was just... meh. Frankenstein but not done especially well, I guess.
The show should always be rising in threat and scale. The previous series Big Bad was a god of a hell dimension. This season it was three nerds. Not to mention Buffy's pathetic existence as a single mom working in a fast food restaurant. Surely the ultra rich Watchers Council can afford to give her a paycheck for saving the world over and over? Also, no Giles. Oh and this was the season of Buffy boning evil Spike too. Unforgivable. I forgot about all the bad things that year.
Once you've done a god of a hell dimension, how do you rise in scale from that? When they tried topping Glory in Angel Season 4, it went very poorly.

(Though I guess The First was bigger too, but I haven't gotten there yet) The only thing to do was go smaller, more intimate. I like what was said about the real "Big Bad" being real life, and strained/failing relationships. And do you mean that Watcher's Council that Buffy very dramatically told to get out of her life, that she was taking control of things? They seemed a very petty bunch, I'm not surprised they didn't bother to support her.
I can't agree about Buffy and evil Spike - it was sad, but made so much sense too. She was cut off, dealing with a hell-like existence, and he kept throwing himself at her.
The reason for the hate is because nothing felt right and none of the character beats made sense.
Willow getting addicted to the power of magic makes sense; going to a crack house to shoot up does not make sense. Xander's life finally coming together with his job and his relationship, but throwing it all away over fear of becoming like his father does not make sense. Giles randomly disappearing for no god damn reason to force Buffy to stand on her own two feet after a severely traumatic life experience does not make sense. Dawn randomly deciding to become a kleptomaniac (which is ignored and forgotten after a few episodes) does not make sense. Tara's random death caused by a physics-defying bullet fired by a gun in a Mel Brooks film does not make sense. As for Buffy and Spike's arcs, well, they do make sense, but they sucked.
Well, with Willow it wasn't just a random crack house but a huge source of power, and she was in a very bad place at the time, plus Amy convincing her to go for it. I'd sooner criticize her deciding to put the whammy on Tara's mind in the first place being out of character, but even that makes sense based on some of what Dark Willow was saying.
With Xander this was actually foreshadowed pretty heavily, imo. Even as far back as dating Cordy we get a reference to an awful family life, and it took him a long time to tell Anya he loved her (and then only when indirectly pushed to it by Buffy). Even after proposing to Anya (right before they might all die) how long does it take him to want to admit it? Even just before he leaves Anya, he doesn't say "We're done" as much as "I'm not ready, and I should have said so a long time ago." And of course seeing a father like that would have a huge impact on him in a way he might not expect.
I don't necessarily agree with Giles leaving especially considering the timing and learning what Buffy was going through, but his reasoning makes sense, and certainly Buffy was more and more relying on him. Which makes sense, he'd always been a surrogate parent and especially after Joyce died, but his reason for leaving fits the general theme of the season, imo.
A lot more could've been done with Dawn's kleptomania, I agree with that. But even from what little we saw: people in her life kept disappearing. Her mom died suddenly, her sister died saving her - and then was brought back, but emotionally cold and distant, her "surrogate older sisters/mothers" that she adored broke up and one moved out. Riley's sudden up and leaving seems to have affected her. The first boy she fell for and kissed turned out to be a vampire trying to kill her (and well played on that decision, Joss & co). Even her own nature probably haunts her as being impermanent and ephemeral before she was summoned into being with a rewritten backstory. So she takes stuff and keeps it, because it can't leave her. Dawn's pretty consistently shown as somebody that craves affection and validation and belonging, latching onto Xander, Riley, Willow, Tara, even Spike.
The physics of Tara's death are slightly wonky, but not in any sort of unbelievable way, imo. And certainly nothing there is wrong in terms of character beats.
I think "Reality Ensues" would actually be a better trope.