If anything we have too many tags. Why should anyone be expected to know that “penetration” is a tag? We already have a tag for “explicit,” “sex,” “intercourse,” “fucking,” and probably several more I don’t even know. (Several of those should just be merged to “sex.”) So how finely do we dice up what’s making it explicit? “Penetration” is not even (oh, not by far) the most obscure tag we have here, but it’s pretty obscure. I never even knew it existed until today, and I’ve been here several times a day since Ponibooru went down. Literally nobody knows all the tags, so while there’s little excuse for ever missing something like “explicit” and “ponut,” literally anyone may miss some boutique tag that matters to a only tiny handful of users. Knowing it exists I’ll now tag it if I realize it’s missing, but that’s never what I’m looking for (positive or negative) and realistically I’m not normally even going to notice if it’s there or not.
If a tag matters to you and is not one of maybe the top 20 tags or so searched, then much of the time you will need to be the one to enter it, because you will be one of the tiny handful of people who even knows it exists and thus can enter it. Then you will not see that image again. And the three other users on the site who give a flying yay! about it will never see it at all. And if all four of you tag “penetration” religiously when you see it left untagged, then each of you will see 75% less of it than you would otherwise. You can get 99% of the rest by spoilering “explicit” and figuring out from seeing the tags on mouseover whether it’s likely to contain penetration before you click through to see it. Problem solved.
One thing I would recommend though is the ability to add tags from the thumbnail. I can mouseover and see them (and see that something obvious to me is missing), but needing to go into the image page and get a full-screen faceful of the image to add it is a remaining problem at least some of the time.
