"what if the idea was to have a person or structure on top that would be fully visible from the same locations? So instead of only being aware of it if you knew where to look, something would be obviously protruding above various bits of landscape around Avebury"
Something like a Stonehenge prototype... I know, it’s been suggested before, but if there’s one thing imho that would sit quite comfortably (and aesthetically) there that would be it :-)