you'd struggle to find any venue in UK that doesn't involve overflying some minor roads or non-participant members of public.
Sunderland (International) Airshow has an ideal venue, with the (non-paying) spectators (who contribute generously via collections and associated purchases) arranged on the shore (and, also, well inland) with the aircraft arriving along the coast (with the occasional approach from inland).
Over the years the display line has been moved further and further out (it is no longer possible to get soaked by a Harrier hovering - even if they were still around), but this means that you see the aircraft for longer as they spread along the skyline.
Shame that we are no longer treated to supersonic bangs from Lightnings (as we were at Acklington back in the 1950s).