I would think that this would go well with a rotor/piston/etc. system instead of being its own device. Limit weapon firing arcs to a few degrees, allow weapons computers to be linked to a rotor or piston block and it link the weapon to the outputs on the other side of the block.
That way you could have an internal weapon system that is manually fired, can be fired in all directions, and looks good, at the cost of not being operable by AI.
If we had weapons that locked on and auto-fired, then the game would immediately have shifted in strict favor of capital ships, which we are attempting to avoid. A "Weak" weapon with auto tracking mounted to a large ship would be disastrous for anything under half the large ship's mass, even moreso than AMCs, as the smaller ship cannot find a blind spot if the entire ship is coated in these things. I suggest avoiding suggestions that allow "Sit and shoot" gameplay to be easy.