Stonehenge Simplified would be nice to see, but it is so very involved, and the data throws up changes to the plan all the time, making it an everchanging project.
The Stonehenge People by Aubrey Burl is excellent reading, if a little longer than you really want, but it sets the background and history of the site and the surroundings so perfectly. Hengeworld by Mike Pitts is also excellent if a little swamped with data.
Unfortunately with timber rings, buildings, postholes, stoneholes and pits spread over 2000 years or more, plus the surrounding landscape, there's rather too much to easily simplify a summary.
Which makes it so compelling!