If the vanilla BF2 doesn't do much for you, have a look at this then:
http://www.realitymod.com/
[ame]http://www.youtube.com/watch?v=xyaBbLoaKH4[/ame]
Its a realism mod for the BF2 engine, forcing you to work as a squad and an entire team, instead of lonewolfing it like 99% of BF2 players. Everything from bullet drop (a new feature) to flying choppers is changed to make the game feel realistic.
You can also play Insurgency in which Bluefor has to find weapon caches around the map, while the insurgents/Taliban have to defend. Brilliant fun and a nice change from flag capturing.
[ame]http://www.youtube.com/watch?v=g2Jt0rREE9Q[/ame]
There are quite a few of us in the FPS:X channel that play Project Reality. Have a look at this video Mildhotsauce put together:
[ame]http://www.youtube.com/watch?v=m9IQleg_Wno[/ame]
If you want any help setting it up, or know more about it. Drop into the FPS:X channel (I'm on around 6pm GMT) and annoy me
