I think it would be cool to have an Ultimates book featuring:
T'challa
Giant Man (Pym)
Mr. Fantastic
Iron Man
Incredible Hulk (Banner)
I would have them function somewhat similar to the last iteration of the Ultimates but with the biggest A list brains in the MU. But they would operate in concert with the other Superhumans. Basically they would be like the Fantastic Four but their mission would be to uncover pending threats to the MU rather than pure exploration.
So say Reed uncovers so parallel universe that's hostile. He calls these guys and they go and make sure the alternate warlords know not to even bother with Earth, because these are just five people and there are thousands on the other side of the portal just like them.