I recently had an idea on the Recoloring Flags thread for how to completely rework how flags are structured. it would be a sort of checkbox system to give more information about why a post was flagged.
Say a post has really bad grammar. you could click the "flag" button and it would open the checkboxes like shown below:
Mark the problem with this post:
[x] bad grammar
[ ] inappropriate
[ ] spam
[ ] all caps / too much caps
[ ] troll post
[ ] opinionated / not answerable
[ ] duplicate
[ ] other: ____
Get it? i think that would be a lot better than just a basic flagging system. The proposed one would show a lot more about what specifically may be the problem. Obviously, mods and editors and maybe experts would be able to see the reason for flagging, along with the person who posted the flagged thing to help them fix what may be the problem. I'd also suggest encouraging [even mandating?] a person who flags something to comment or publicly say the reason so that troll flagging would be harder and so that other users can see what and/or how the post is doing wrong, and then they can make sure to not make that mistake themselves.