Elhoim
Iron Tower Studio Dev
Ok, different idea:
Fort provides LOS +1, and upgrades another LOS +1 with each of Iron Working, Optics, Chemistry, and Flight.
A Sentry Promoted unit on a hill in a fort in the Modern Age seeing 7 squares seems fine to me. That might provide a little advance warning in key areas.
That´s a good one. I also think that they shouldn´t replace other improvements... Perhaps a model that goes around the lines of the tile would look good...