Hmm. It would have to be something like an Archon, something without physical form of its own. Remember that the Angel in the Trenchcoat is using a mortal human named Jimmy as a host.
As for the powers... Can't be done. They all have Teleport, but none of them could take a host with them. And he occasionally took the brothers and their allies with him.
Healing is okay, they can all do that. He would occasionally Resurrect the brothers, and others.
"Angel Radio" type telepathy would resemble Contact Other Plane more or less at will.
Immune to mortal weapons would be done with a high DR/Piercing + Good.
He had and used Invisibility, as all the Angels did. Invading dreams sounds like the Nightmare spell (though I'm sure there's a better fit).
The "Smite Demons" thing they did looked like Dispel Evil.
Most of the rest is attitude and RP.
Over all, you're going to have to custom build a package.
