Either there isn't a standard format for POV tags, or nobody's bothering to follow it. Let's look at the biggest issues I've found when searching through the tag list:

Fellatio

The tags for POV giving head and getting it, respectively, are called fellatio_pov and pov_blowjob for some reason. Neither one is clear enough in its meaning and the two formats don't match. Miraculously, almost everyone seems to be using them consistently; I can only spot a couple outliers. The first one does at least have a wiki page explaining correct usage.

Recommendation: Bulk-update all of these to "giving_fellatio_pov" and "receiving_fellatio_pov" respectively; do a quick search for mistags and clean them up; rebrand both original tags as invalid disambiguation tags.

Footjob

The tags giving footjob pov and receiving footjob pov both exist and make up the bulk of posts. However, pov footjob and footjob pov also exist.

Recommendation: Go through the latter two tags and retag everything properly, then rebrand them as invalid disambiguation tags.

Cunnilingus

In this case there's only one tag, called cunnilingus pov, and it does seem to be used exclusively for the POV of the one with their face in her crotch. Which is weird. Where are all the POV shots from the one getting eaten out? Here's one; I found it because I happened to click on a picture that has a parent. It's also got the receiving pov tag on it which is not how that tag is supposed to be used.

Recommendation: Find where the hell all these posts went, tag them receiving cunnilingus pov, then bulk-update the others to giving cunnilingus pov and brand the old tag as disambiguation.

Facesitting

At least there's only one POV this could refer to, but the redundant pov facesitting tag does exist.

Recommendation: Alias pov facesitting to facesitting pov and call it a day.

Other

There are various tags formatted as "pov_thing" rather than "thing_pov". Not a big problem or a high priority, but providing a consistent example of correct formatting can help prevent people from creating new redundant tags in the future.

Recommendation: Create aliases for these.