Arrei said:
Yes, that's where my point from earlier comes into play. In small numbers, such pools tend to be allowed to keep existing, but when they become too populous to handle, they can't be ignored anymore so they get culled.
So it's not so much that they're subjective, it's subjective and they have a lot of posts? ...so if people add an arbitrary number of images to subjective pools they suddenly become a concern? I mean, I'm guessing it's not a lot of work deleting a pool, so I don't see why there needs to be a size for concern or not, simply a statement of the reason a pool is kept or deleted. And in the case of these perfect pools, the reason given is that they're subjective.
And if it IS simple to delete pools, there's no reason to allow pools breaking guidelines to simply be allowed to exist just because they're small.
...but as the only one of the three "adorable" pools to be based on a subjective quality like "the cutest", it seems to not be enough of an issue to really get anyone to bother with it. (Badass and Unhappy Adorable are, at least, intended for any fusion of the two themes, rather than a measure of "how" cute it is)
Even "Badass Adorable" though, for instance, is a fusion of two subjective themes; Badass is no less so than Adorable, let alone Perfect or Sexy. And if any of the concepts are objective enough for us to define (say we say Unhappy is definable), then making it a tag combination seems to be the way to go. So even if Badass was objective as well, which it's not, then the pool would just become the tags Badass and Adorable, and you'd find fusions of the two by searching for the two tags together.
Sure that might not find someone that's being badass and adorable because separate people are being badass and adorable, but we don't have "Blonde Girl" pools just because blonde + 1girl might find girls without blonde hair due to blonde haired men being in the picture.
On the other hand, several of your listed examples fit firmly within the intent of the pool system. Almost Heartwarming, for example, is for any depiction of an event intended to invoke heartwarming feelings followed by an abrupt about-face in the mood, without getting subjective criteria like "how" heartwarming one thought it was in the mix. You could technically make that a tag, but it'd be so specific it'd be nearly useless in such a form.
What makes a tag "too specific"? There are only 2 pictures tagged "meat_cleaver" on Danbooru, so if it's about specificity does that mean it should simply be tagged "knife" and any that are specifically meat cleavers should go in a small pool devoted to meat cleavers?
If that's not what you mean by "specific", what do you mean then? If you say it's definable enough to make a tag out of it, I know of no criteria that says it ~shouldn't~ be a tag.