On firing arcs: One of the big sales pitches for the RTS game
Supreme Commander is the way weapons work. Some units may have powerful shots, but are slow to turn, and so a fast moving unit will make a dangerous foe. Not because of a random dice roll modifier, but because the turret doesn't turn fast enough to keep the rabbit in it's crosshairs.
I hope that firing arcs have the same sort of effect in overall vessel performance, design, and use in combat. It does present a new componant size consideration: Ships will need comparatively more weapons, and AI will also have to consider turning ships to bring weapons to bear.