The Guardian reports an research framework for the near future study of rhe area around Stonehenge. The immediate vicinity of Stonehenge (about 2000 hectares is designated a World Heritage Site) is full of ancient graves, many of which have never been excavated. A grave about 3 miles away revealed the cotemporaneous "Amesbury Archer," whose childhood may have been spent in the northern Alps, and whose rich burial ornaments came from as far away as Spain and France. (see links at archaeology UK) So the possibility of learning a great deal more about European Bronze Age culture is very great.
The framework would like to begin new small scale digs, and increase efforts to retrieve artifacts which have been taken from the site by any number of means. A timeline of historical digs is here.
For a very good summary of issues related to balancing science, public access, and preservation in a World Heritage site, see Save Stonehenge .