This is why, in my opinion, Star Wars Battlefront II is the best PC Star Wars game for fans.
The game has three modes: Campaign, Galactic Conquest and Instant Action.
The Campaign starts you off as a clone trooper telling his story about the history of the 501st. Halfway through the game, you become stormtroopers.
In Galactic Conquest, you choose between four factions:
Rebels
Droids
Republic
Empire
It goes Republic vs Droids and Rebels vs Empire.
Your goal is to beat the other faction and take over the 12+ planets in the galaxy.
Instant Action is simple. You get to create your own sequence of battles ranging from types like Capture The Flag, Assault/Conquest (normal battles) to XL, a 300 vs 300 battle.
I'd give this game a 4 out of 5 stars. But that 4 can improve to a 5 with free mods.
The only one you'd need to make the game so much better is the Battlefront III Legacy. It's not finished, but it's in open beta. The only map it includes is "BF3: Coruscant" and the developer is making Bespin right now.
The mod improves graphics and adds ground to space maps. It only does this with the maps labeled "BF3: