Since it has been confirmed here, that you can reduce your Threat with the Vanish from Sight + O Elbereth! Gilthonial! combo, I figured, why not try to build a deck that makes use of that.
Now, this is still fairly tame and not trying to completely breaking the game with Wandering Took and Song of Eärendil. It should be fun to play, after all.
The general idea is to have a nice start thanks to Denethor, who will then be used as a defender (or even take undefended damage), until he dies. Elrond will gladly take over as the Steward of Gondor (during the first turn even, if possible). Once that is done, Vanish from Sight can be used as the requirement for having no more than two heroes is met at that point.
And since we are resetting our Threat down to whatever the encounter deck has to offer to us, anyways, why not take the two highest-cost heroes with us.
That's pretty much the whole idea here. The rest is just good stuff to use with Elrond and Gandalf. With the resource generation thanks to Steward of Gondor and Resourceful, as well as Vilya, the deck should be able to get any cards on the table. There's some extra card draw with the Expert Treasure-hunter (so good with Gandalf), just in case there are too many resources around.