As I've said before, most of season 7 should be taken out back and burned.
That said, if you were approaching the series from what I will call a feminist angle,then you should have had a problem with the series from the get go. In other words, feminism, in the series, is defined in masculine terms, so Buffy as the warrior.
Now to include some others, and you, I think the Anya part was fine. She was perhaps the feminist hero of the series. First the lover, then the lover scorned, then the queen of vengeance, then His Mrs., i.e., no identity save for male him [think of not so long ago when your name, if you are female, would have been, if married, Mrs. male given name, male family name], then back to scorned once again, then she thinks she's nobody, and then she works out finding out who she really is. And unlike the survivors, she can say, greater love has no human than this, than she lay down her life for her friends. And note that this time, unlike the first time, she didn't bag out of town. So they did her just fine.
And there was crossover here as well, understood by the masses or not, meaning, for how long was she a vengeance demon? Longer than Angel/Angelus was a vampire? And so note Angel's discussion with Harmony, when he's contemplating his own end and he basically says that he cannot even truly remember what it was like to be human. That's what Anya was working on. Again, they did her just fine.
And no reason to go beyond Selfless, other than the quest for who she is, now. We already had all we needed. As I've said before, the true test of Anya's new found humanity would be, wait 'til she's scorned again, then we'll see just who she is. So she was scorned in season 6. As we saw, while she wasn't exactly thrilled with Xander following, she did help out with respect to Willow, was troubled when she saw Warren flayed, and then we have season 7, where she tries to be the old Anyanka but that just her anymore. And, for irony, she's the one of the rare few persons in the entire series who ever accepted personal responsibility, and in her case, in the context of what she thought would be the end of her own life. Faith did so as well, but she did so in the Angel series. Why I've all the love in the world for Anya and Faith.
Now on to deus ex machina, what was the point of Andrew? Ensouled Angel in search of redemption, check. A contrite and repentant Faith in search of redemption, check. A second time human looking for her own redemption Anya, check. So what was the point of Andrew other than some lame attempt at comedy relief? Let me put it this way, I wanted to hurl every moveable object that I own at the TV screen when we got to that part about Vulcan versus volcanologist. And not to insult the Chinese, but what the point of our gal from China chiming in on Faith's doing gymnastics in the backyard there, other than, in context, her statement illustrating perfectly the singular irrelevance of Andrew (she didn't understand his purpose in the series and neither did I).
Now back to Buffy, I will assume unless informed otherwise by those responsible for the show's content, that one of the reasons, note the use of "one", for the Potentials and the Willow spell was the problem of isolation, i.e., Buffy's isolation. I was hoping, well, recall the scene wherein Buffy is having her moment of extreme doubt after being almost beaten to death by one of those uber vamps. So I was hoping that here was the point of the story when Buffy finally understood that we're all alone, at least in death, since we go through that alone, no matter how many are present at the time. And her friends, the mere mortals, had faced death, probably understood the notion of impending death, and so they too knew what it was like to be alone. So if she was isolated, the choice was entirely hers. And so I was hoping that she'd finally realize that. And act accordingly.
And now re the ending, yes, you are correct, in part. Although I too have made the point about some not getting a choice, the more disturbing issue for me is, well, think of it this way, Joss might as well have said that he has no moral concerns about our use of data from Nazi and Japanese experiments on humans. A gross violation of the human rights of those persons, so too with our first slayer. Yet Joss desires that we profit from what is tantamount to her rape.
Now, re Caleb, I found the idea behind him simply laughable. Apparently, since the Catholic Church isn't exactly fond of females as priests, they hate women. Strange that. Given that after Jesus, is Mary with a rather large cult of veneration and devotion. So be a good boy, Joss, and say ten Hail Marys. By way of your penance. And by the way, so much veneration and devotion, in fact, that we rarely hear of any Jesus sightings. Meanwhile, people all over the globe are claiming yet another apparition of Mary. In other words, Joss, long before you came along, the Catholic Church was using Mary as the vampire slayer (for more than a thousand years). Of course, Mary isn't exactly the warrior type. She instead slays via the notion of pure of heart. For more on that...
Next, re Spike and the amulet, remember, Spike claims to have wanted his soul back for Buffy. Is in Chosen that we see the greater reward. Here, note what Buffy says, she tells Spike she loves him, the one thing that he's wanted for a while. He says, no, you don't, but thanks for saying it. Then we have why Spike and why the amulet, and the truly cleansing power:
SPIKE
(amazed) I can feel it, Buffy.
BUFFY
What?
SPIKE
My soul. It's really there.
One of the ironies of the show, as Joss himself admits, is that he is an atheist, yet a goodly amount of the series hinges on faith or religious notions. Note the intro to Chosen, Spike on the cross, with the fire burning the cross into him. So his reward, for getting his soul, and then becoming a loving and selfless human isn't Buffy's love (though, again, that's what he thought he most wanted). His reward is instead Deity's love. And so Deity grants him the best of all gifts as his reward...My soul. It's really there. And remember here as well, the first thing to be cleansed would be the demon inside him. And on that note, note as well, when you watch the ep again, the change on his face from one of surprise, etc. to one of joy and happiness, as he experiences his soul (his cleansed soul). Then note that in the consummate selfless act, although Buffy says that she and he should go now, he stays. Spike on a cross. The clean soul dying to save us all. And not as devotion to Buffy, but as devotion to cross and all it represents.
And note the other element here, the man playing the presumably feminist role, meaning, Spike didn't actually kill them. Their own evil state(s) killed them. All Spike did was shine a light in the darkness. No more darkness. The non-violent way to achieve justice. And back to Spike and Jesus, both on a cross, what was it that Jesus said? I am the light of the world... So, again, Spike as Jesus on a cross, shining light into a world of darkness. A fitting Buffy end for Spike.
Lastly, back to Caleb. Caleb's power is as much perception as reality. Remember, the little engine that could didn't get over that hill by thinking it couldn't. And so the greater Buffy's faith, in herself and others, the weaker Caleb became. One of the other subtle and worthy messages of season 7. In other words, the more faith and love you have, the stronger you are and the weaker the evil are. And don't forget to shine some light in the darkness. You might even feel your very own soul. I didn't say it, Joss did.
