Essentially the title; a list of tags to be included in every search, to complement the blacklist system.
I was trying to think of a way to actually mitigate the blacklist hiding things rather than removing them from results entirely, and saw that we can actually use up to 40 tags now. I definitely don't use that many, but I do often end up using exclusions to remove things that end up leaving me with maybe one in five images actually showing. This also means that I end up scrolling through the search text if I need to remove or add specific text. So would it be possible to add... well, I guess it'd basically be a whitelist. Even if it was limited to 5 or 10 terms to be automatically applied, I think it'd be really useful for people who tend to have certain terms in every search (like a preferred order, for example) and act as a partial solution to the problem of the blacklist sometimes leaving people with a huge number of null spaces. While it can be done manually, it clutters the search bar and gets tiresome adding the same terms over and over.
Obviously this would mainly affect the search bar and results, and would help reduce complaints about null spaces from blacklisted images, assuming people used it. I think people would appreciate having the workaround.