I like the way you moderate this tribe and have been working with others to moderate the #ReggaeSteem tribe (#jahm token). Although it's not as serious as STEM, we don't tolerate off-topic, spammers or extremely low-quality content.
Moderation is definitely key to success, I've noticed some communities don't care and have abandoned their tag, I am glad you haven't. There also needs to be a discussion about rewarding new content to set an example and directing quality. Carrot and Stick method.
Your methods are interesting and a version of them may be implemented in the future. Sometimes I do like to give the reputation hit to the abuser to make other tribes know of this. I also hope that your universal blacklist proposal gets published. It's likely that many of these abusers go from Tag to Tag like vagrants never finding a home because of poor behavior.
It would be interesting to see if I could write a post that uses both the #jahm and #stem tags. I feel like one tag would be a stretch. Here's an article https://daily.redbullmusicacademy.com/2012/06/computer-rise
“Computerised riddim haffi make the crowd rock...”