From my understanding, the Enclave has an outpost in Chicago that could viably be used to further their role as a Superpower in the series. Some may argue the Outpost is small and undermanned, but how do we know it doesn't look like this?
http://images.wikia.com/residentevil/images/2/20/TheHive.jpg
http://images.wikia.com/residentevil/images/f/fb/Hive.jpg
As a playable race, those born into the Enclave could have special perks/advantages that uniquely distinguish them from the common wastelander.
Here are a few perk ideas:
Enclave education = +10 Science/Medicine/Repair/Speech/Energy Weapons/Advanced Technologies (Computerized Weapons ie. Machinegun grenade launcher/ PA efficiency)
Enclave Upbringing = +1 INT/CHAR/PER
Unadapted genes = -25% RAD resist/ -50% disease resist
Another obvious advantage to playing Enclave, would be membership in the Enclave faction. And the only way to be a member is to be born into the Enclave. With joining also comes a unique beginning and possible storyline for the player.
Still, if the player chooses to join the Enclave but then has a change of heart, there should be the option to leave the faction and integrate into the wasteland.
That's my take on the matter.
Thoughts?