For example: What about "color"/"colour" and "black and white"/"black & white"? What's the intended use for tags, anyway? I saw that it's a filter criterion for the Awesome Button as well.
the purpose of tags is finding a shot you saw a while ago without having to browse through the archive. We had the color/colour discussing a while ago, but nothing really came out of that. However, i don't think it is good to tag shots with color, because almost every shot is in color, and then you still have to browse trough a lot of shots if you're looking for a particular one. Tags are not a way of giving hints, so no actor names/characters etc. Hope this helps.