I unlocked "Tod" for cannon upgrades. Still building a few more mats before I go back there. I was looking at "rapid fire' thinking that's the most useful since my main ships I use for battle are the Anaconda and Federal Gunship. Neither turn that great and both have large multi cannons, grades 4 and 3. My logic is putting the most shells on target while I can. I'm interesting in hearing from someone who's done cannon upgrades and see what you guys think.
Thanks,
AirBear
Thanks,
AirBear