Just had a look at the spectator guide- does anyone have any hints of which stage to go to for the best action?
It'll depend what you mean by best action, it looks like three very distinct stages.
You could try searching Flickr for "tempest rally " followed by the name of each stage (one stage name at a time) to see what they look like as they're likely to have been used in previous years. And the same on YouTube should bring up external footage and onboard footage.
I've never been to any stages in the South but looking at the maps in the spectator guide:
-Warren looks similar to a lot of the Yorkshire forest stages so I'd guess that's going to be the typical forest rally type of stage.
-Pavilion is very straight which will be dull other than possibly getting to see the cars on the limiter, but looking at the spectator approach route the spectator area is probably near the few corners at the end anyway. They don't seem to have marked the actual spectator area on that map however. It's got "Royal Pavilion" marked near the parking so I guess it could be a country home type stage - which could be set up in pretty much any way a rally stage possibly could be.
-Rushmoor looks like a super special/spectator stage/spectator special which normally means there'll be a lot of cones, tape, hay bales and things of that nature. The name Rushmoor
Arena suggests you can probably see a lot of the stage, if not all of it, from one position and the loop layout suggests the cars probably go past more than once as part of the same stage.
Based purely off the maps I'd pick Warren, but I haven't checked Flickr/YouTube to see what the stages look like.