I agree, this needs some work to allow us some administrative control. Tags are easily misunderstood - people often use them like search keywords and they are most certainly not. They are site/content-relevant terms that are more like pre-chosen Categories. I do see the need to either (or both) a) limit the Tags, maybe setup a manager approval Role so that all tags are suggestions, and b) we need a way to aggregate the Tags; when I want the word "Seniors" to appear in the Tag cloud, I should be allowed to assign that as the Primary Tag that matches "senior", "seniors", "senior citizen", "elder", "elderly", "senoirs" (note the mispelling), etc. It makes no sense to have a Tag cloud filled with words that all mean the same or similar thing. To me It does not seemuseful to the user to click on the Tag "seniors" and not see articles tagged with "senior citizens" which I have happening now (and fixing it manually is time-consuming to say the least).
At the point where you enter the Tags, there is currently no way to see the existing Tags, so if you are thinking and inclined, you can't even see whether other articles are already using "senior", "seniors", or "senior citizens" - make the wrong choice and you make the problem worse. Am I making sense?