Great analytics, piss-poor analysis. You need to look at the POSTER and the VOTERS. I think you will find that most times, the unique tags are by hi-level users with good followings (which you are not) and/or any user that bots their posts heavily (which you are not). The well-used tags will make one pop up in areas (UI of long time users) that will get you noticed. Steem is a "war of attrition" and you need to get consistent hits and the very, VERY BEST WAY to get a Following is...
RE: Tags. Stay off the beaten path.