Hero of Avalon

If you're like me, and enjoy space battles too:

Build the standard mix of all different kinds of units. For space battles, wade in with your cruisers and frigates first (as they're your most durable units--especially the Rebel ships), escorted by fighters and bombers. Leave your corvettes in the wake of your heavy ships and when your opponent shows his face, bring them to whatever attack angle the enemy reveals their bombers on. Once you can see the space station--or, if you're the defender, the enemy's flagship--take your bombers off of escort duty and go straight at the most appetizing hardpoint. If you're the Rebels, I recommend locking your B-wing's s-foils and diving straight at the hangar to cut off the flow of reinforcements, or the shield generator so your cruisers and frigates have the upper hand. If you're the Imperials, go for the engines, turbolasers, and ion cannons first.

Corvettes are also a primary target, as they're the most serious threat to your fighter escorts. If you want an advantage in fighters, have your frigates and cruisers engage your opponent's corvettes, while your bombers get up close and personal with the enemy capital ships (to prevent the enemy from doing the same). Don't worry about your heavy ships, your corvette escorts can fend off fighters on their own.

To make quick work of the enemy space station, replace all ships you lose in the opening wave with your respective missile corvette. Let your heavy ships close the distance to spot for your missile ships, and volley your barrages on the center of the station. Focus on the torpedo launchers or, most critically, the hangar bay (This is especially true when the space station is level 4 or above). Don't worry too much about the shield generators, as once they're down, they take awhile to build back up.

When you're on the defense in space combat, build your upgrades to the max. Make sure your border planets have a planetary weapon or two to supplement. The more planet-side weapons you have, the faster they recharge, and the more effective they are. Even level 1 space stations can be formidable opponents when up against four planetary ion cannons or hypervelocity guns.

On a galactic level, the general rule is to only worrying about bulking up your forces on the border planets. Your worlds that are further from the conflict can be used for troop training and army building. The furthest of your worlds should serve as bases for mining operations to increase your income. Station your main fleets at your worlds with the weakest defenses (for example: Dagobah, which has only two space station slots and two ground base slots). Do your best to acquire planets that are heavily fortifiable.

The guy above me pretty much covered how to win a war on the ground. But lots of T-2B tanks are tough to beat en masse. Even AT-AT's can't bring enough firepower to bear against a hoard of 'em. Field commanders are nice to have but not necessary. Artillery is fun, just so your shielded tanks can hold up your enemy and bombard from afar. Bombers are a good idea for attackers (and are one of the only immediate advantages available). The defenders should build up shield generators and go hunt for build pads. Use sensor nodes to act as spotters for your artillery and use those locations as central points of defense and fall-back zones if your opponent proves to have some aggressive tactics in their favor. If you have some free infantry that you plan on sacrificing, throw them at your opponent's landing zone, and if you're lucky, you can cut them off and end the battle before it starts. You only need to construct anti-air turrets in remote areas near the edges of the map, and maybe one in your base. Keep them well out of the way, and your enemy won't even know they're there.