Is there a useful difference between the tags propagation and range? It seems to me that “range” is a sub-topic of “propagation”, and one which is not sufficiently specifically-of-interest to be worth tagging (in fact, it's somewhat characteristic of bad questions).
I don't really think this should be done. Propogation seems to refer mostly to DX type contacts, while Range could also refer to point-to-point. In fact, most tags with range refer to point-to-point range, and I think they deserve different tags.