The player should be able to aim at his targets himself, tell his units to do so and build supporting structures at stategically important points.

A really old game which comes really near at this concept is Uprising 2: Lead and Destroy.

The project is in planning right now and nothing has been implemented yet.
If you're interested in contributing, have ideas or requirements for this concept or want to help out coding, please write a blueprint or do not hesitate to contact the project owner A. Götz.