I would not mind seeing a very durable but energy costing gun mount that turns your fixed angle weapons into rotating. So lets say for the cost of 1 energy you can turn your, tsunamis, executioner, porcupine etc what ever fixed angle weapon you want into a rotating weapon. The gunmount would be small so not to use them as cheap armor with probably 800 to 900 durability with probably the same rotation speed has a cyclone.
Edit: I think a better idea with the durability part is just to make it the same as whatever the durability of the mounted weapon is. So if the mounted weapon is lets say a executioner than the mount will also have the same hp as the executioner and if either one goes than they both go. I think that would solve the using them has cheap armor issue.