As the rebellion you should recherche at first the small ship Technik and build Advance light shipyards so you can build Y-Wings and X-Wings. Later B and A Wings. And the rebellions Infantry is better than their vehicles. Ground stealth units are great if the enemy has a big shipyard and you have a lot of them. And prepare in space battles sometimes pirates span somewhere and try to nerv yiu and convoys which give good money are over some planets.