Wow, Phoenix, I think you have some deep stuff going on here. I quoted the section above because I both agree and disagree - I think that the idea of control of knowledge as power is a great one. The cat is out of the bag - if ever the demons of the world were on alert against goodness, it's right now. They are all looking over their shoulders and trying to expect what they can't know for sure.
I'm not as certain about robbing people of their right to choose their lives... I do agree with your point, however, I also think that each of these girls was robbed of that right when they were born and thrown into the pool of "potentials." Prior to Willow's spell, any one potential at a time could have been forced to choose the life of a Slayer... but only one at a time. Regardless, at the death of a Slayer, the new one is forced to choose. Waaaay back in Season 1 we saw initial resistance from Buffy when she learned that Giles was her new watcher; she thought she'd left that part of life behind (just for a second). But ultimately she discovers that she really has no choice. Is the crime any greater if it happens to the multitude suddenly, rather than trickling down to possibly 20 or 50 over a single generation? (This point is more for discussion - I can see that there are a lot of ways to look at it)
I think that the scales are considered tipped because the initial balance was a ratio of 1 Slayer: Infinity Demons. That's what was established as a baseline "balance." Even though we're looking at even numbers now between Slayers and Demons, with more produced all the time, we aren't looking at the previous template for an established balance by any means.
Also, I love the idea of the First Good. We complain about Him/Her all the time in real life - so why doesn't He/She/It fix everything or support the Slayer more if He/She/It exists in Buffy's world? Who knows? I suspect it comes back to an issue of free will and doing the right thing for the sake of others, rather than expecting a reward to come down from the First Good (if there is one). Kind of a typical Judeo-Christian answer.