How do you take over as admiral

Not sure if the quit game is the right thing.

Is it better to build up my solar as high as i can and get rid of my fusion so i can use those fusion upgrades for other buildings or shoudl i only upgrade my fusion and get rid of solar but then i got to upgrade my gas mine to comensate.  I am unsure of which one is better to keep upgrading?  Can i get some thoughts on this please. 

How cruisers are needed to kill a Death Star? Any one know?

I have information to add to a  Cost/Rewards table but don't know how to edit it to add the new information. Can anyone help?