I wouldn't mind some sort of Autumnist Enclave poping up, but nothing major, and Styles crack open some wild theories, I agree with them sort of.
EDIT: Ninja'd, good on you Styles bringing out your most beautiful theories involving the MWBoS
The only wild part about my theory is that the Enclave would finally knuckle under and join with another group. I myself would not mind them simply dying out or becoming a smaller faction just living day by day doing something else besideds trying to take over the world. I mean really they have tried twice. The first time they lost their whole civilian leadership. The second time it was just Eden and nothing but military people and military can't be president. They died again. There really is nothing left for them but for Chicago. An outpost most likely built by the Enclave from Navarro on their way to DC.
Midwestern Brotherhood have been in the Chicago area for over 80 years. They haven't made contact with the original BoS and Fallout 3 says they had "fallen on hard times." With possibly new evidence from New Vegas that hints that the Legion is making contact with BoS in the East. Legion are in Colorado and the Midwestern BoS made it to Colorado. That could be evidence that the Midwestern BoS are now reduced to strongholds across the Midwestern United States.
Anyways the Enclave are in Chicago and the Midwestern BoS are in Chicago. The two had to have crossed paths and I doubt the remnants would have been able to wipe out the Midwestern BoS. The MWBoS would be interested in the Enclave's tech and as a bonus, the MWBoS would not know of the Enclave for they left before Fallout 2. I am hoping that the Barnaky Ending is the Canon ending to Tactics even if the Enclave have nothing to do with it but I can see a role for Enclave remnants to be apart of the MWBoS. I only started working them into the theory when Ed-E told us the Enclave are in Chicago.