Alright I've got a final design
she sure as hell ain't pretty but she works, she has 5 extra cargo bays, travels between each planet in 2 minutes, has full turret coverage and only a 2 minutes of downtime between planets to get to 300 ammo because I stockpile 15 metallic asteroids in the bay so she can take the trip back and forth regularly without stalling in orbit with minimum downtime no matter the asteroids that spawn. 750 space scaffolding is pretty steep for the earlygame but it's going to be a pretty decent cruiser.