questions about tagging

Hey all! I am coming to you with the following questions because I've reached the kind of impasse where there's a manic squirrel running around in my head and there doesn't seem to be an answer that can keep me out of trouble! Please, please, please, even if you never like to comment, even if I intimidate you, please let me know if you have any opinions about the following questions. I might have follow up questions for you if anything is unclear.

Many, many, MANY THANKS in advance!

( two questions about AO3 tagging )

( tumblr tagging )

( DW icon descriptions )

I do have systems that I'm using now, but with all the incoherent and unspecific grouchiness around they are apparently inadequate! I like to avoid getting into fannish trouble because then you just end up on fandom wank for having bad tags and all the old bullshit gets dragged out and trust me, I've been called a sockpuppet enough in this lifetime.