Canon Barrel Block + Canon Firing block + Canon loading blocks + Canon turntable/trainer-elevator
The idea is that instead of having one pre set canon model. The player has to Engineer their Canons on their ship. The barrel block will increase accuracy in an atmosphere, and decrease accuracy and increase recoil in a vacuum. The Canon firing block fires the round, dependent on size of the calibur. The loading blocks can be stacked to increase loading speed and size.
This way we can customize our guns and put plating around it and what not. It is not a one block solution, but gets us many different potential styling blocks and creates Engineering problems.
for the Canon barrels we can have short stubby Space barrels and Long planet barrels for accuracy.