I've gone through the invalid_tag aliases for lack of better things to do and I've looked at a few that I think should be either re-validated or aliased to something else.
Various artists have been removed by their request. I think their names should be aliased to something besides 'invalid_tag' so it's less confusing. Maybe 'invalid_artist_name' would work, or artist_requests_anonymity.
As a caveat to the first concern I could go for 'g-rated_chest' and 'g-rated_crotch' as tags, since they're mpre specifically referring to the area lacking the thing than the thing the area is lacking and it would lead to less confusion, but I think they're clunky tags.
cartoon - alias this to 'toony' so it refers to a particular art style
commission - I don't think this is a pointless tag. Knowing the source AND that someone paid to have this made would be a good line of advertising for the artists whom we so humbly borrow images from.
drawn - I'm not too concerned about this, but it would be good to have a tag that differentiates drawn art from CGI or 3D modeling or watercolors or flash or whatever. I guess, though, 'drawn' is pretty default so there's only a need to tag it if it's some other kind of art.
first_time - this is a fetish for a lot of people, so as long as it is well-applied it should be allowed
fursona - this is listed as 'pointless', but someone's fursona is different than regular furry characters. It is nice to go through and see that this is how someone sees themselves - though admittedly it could be hard to decipher this just by looking at the image.
horror - there are plenty of images on here drawn to invoke horror. Some people might want to get spooked!
genderfluid - I think there is room for this tag. It's not the same thing as ambiguous_gender - it's more of a lifestyle choice than simpley not having titties on screen.
hasbro - this is a trademark that owns a lot of intellectual properites that people here like to draw pictures of.
no_bra - this is a good tag. If you can see the girl's tits free-ranging under her shirt, no_bra is appropriate. A lot of people would want to look for this. It needs a good woki page - maybe changing it to 'not_wearing_bra' would help, but it would still confuse people who jump at 'lack of' tags. Maybe 'braless'? At any rate, a shirt with no bra is a common fetish.
no_anus / no_pussy / no_penis / no_nipples - It's easy to view these tags along the lines of 'no_coconuts'; why go through and tag every image with things that are NOT in it, right? That's not what these particular sorts of tags are used for, though. People use them when you are seeing an image that anatomically SHOULD have one of these parts, but does not. A topless female with smooth breasts would be fairly tagged as 'no_nipples', for example. These tags should be brought back with good Wiki entries - someone has recently been on the forums asking about exactly this & I think they have a point.
panel/panels - should be aliased to 'comic' instead of just invalidated
paywall - this tag should not so much be valid, but flagged in a different way. If this art is from behind a paywall it's probably DNP and the mods need to hop on it quickly.
pervert - this is a good tag for a peeping tom or other horny creep. Again, some people want to see that kind of image. Needs a wiki.
tail - I get that arms and legs and skin (who the hell ever tagged 'skin') are too obvious to bother addings, but not everyone has a tail. Sometimes maybe you don't want to see someone with a tail - or maybe you don't want to see someone without one! As 'no_tail' would fall under the lack_of sort of tags people would not like it, and I understand 'tail' would hit a lot of images here, but there needs to be some way to differentiaate between people who have tails and those who do not.
transgender - why is this a bad tag? It's not the same thing as 'intersex', which is more of a physical thing. 'transgender' is a mental thing, an identity of ones self. Exactly how it is apparent from an image may be questionable, as a girly boy forced to dress as a maid isn't exactly transgender, but I think it's a very important identity issue for a lot of people & should be allowed where appropriate.
whore - not really slut/slutty/bimbo as in the reasoning it was invalidated. it should be aliased to 'prostitute'.
Updated by MissChu