Honestly, it worries me whenever I see such. The reckless use of the trust system for vendetta and intimidation especially by high ranked members is worrisome. I've come across red tagged accounts whose alleged offences were for spam posting (not even plagiarism) but those who tagged them couldn't put references to the tags. I thought the major reason for tags is scam activities on accounts or for threats to life or some other weighty issues. Aside that, I think other tags should be left as a mark of personal notification and reminder in-line with what OP is advocating. I'm in support of this feature OP seeks.