ok so here is my idea... Orb Builder-Orbital HQ *builds around the planet its to larg it takes half of the planet* Orbital HQ-Space Fabber - Space Fatter-Builds orbital Refinery Orbital Shipyard heavy orbital shipyard and Space defenses Orbital Refinery-auto builds metal extraxters with inrange when it is compleated can build Harvetsor to harvest destroyed starships for metal ShipYard can build -Corvetta Troop ship and Missile Cruiser Corvetta-haves a light laser cannon for ship to ship and a AA gun for Anti-shuttle defense Missile Cruiser-Fires powerful missiles at hostile units and planets long reload time long range weak hull Heavy Orbital Shipyard Battleship -2 huge laser cannons for ship to ship and bombarding planets Fleet Carrier no turrets ueses Fighters for defense can hold up to 100 fighter/bombers Dreagnought-3 heavy turrets that can destroy a planet in 4 cannon volloeys Defense Platfouem-Space Station land your commander here and build a base in space! AA Laser towers you name it! (you want a flat map? here ya go) battleon top of it! but watch out caues the owner of the station can send bombers out of it to attack the landed commander! Laser tower-fires a blast a little more powerful then the corvetta laser blast chep and builds fast Ion Cannon-fires a huge bolt of Ion energy that can destroy any ship in one hit long reload time expensive and long build time
So the Heavy Orbital Shipyard would presumably consume a lot of metal per second so it doesn't take hours to build?
If you have something that's that expensive then one of two things happen. 1. You put very little on it so that it's "eventually" finished, but you're still producing units at a good pace. In this case the game is over before it does anything because it takes so long to build. 2. You put everything you have on it to try and rush it out ASAP, sacrificing unit production to hurry it. In this case you're steamrolled before it's done because you don't have anything to defend with before it's out. In order for something to be useful, it has to be affordable or offer some benefits before it's finished. Scale down the cost and effect if you want it to be useful.