Easy money
Conquer or capture all the planets except for the mission planet. Then, fortify the planets around your mission planet. Once this is done, set the game to fast forward and allow it to run. Check on it occasionally to make sure you have not been attacked. After awhile, check your cash flow. If you like it, resume normal play and complete the scenario. If not, just wait and let your money build.
Cheat console
To display the cheat console, hold [Shift] + [Tab].
Recommended Empire space fleet
You must build, to conquer space, as many Accumulator Assult Ships and Victory Star Destroyers as you can afford. You can also use some Imperial Star Destroyers and possibly a Interdictor Star Destroyer. Now that you have your space forces, focus on your infantry. You may need to wait for more income because of all the space forces, but when you get enough, buy some of the first two things you can (for example, Storm Troopers or Scout Troopers), then a few tanks. Note: This will also work for Galactic Conquest.
Recommended Rebel space fleet
Build at as many places as you can, X-Wings for space and Infantry Platoons or Plex Soldiers for land. Because X-Wings have such a high fire rate, they will have no trouble ripping apart pesky enemies. When the space battle is over, take the ground with your forces. It may also help to have some T2-B Tank squadrons). With the Plex(s) as high defensive and your platoon(s) doing the rest, you should win quickly. Note: This will also work for Galactic Conquest.