It's rare in a game like this to have strong consensus on power level but in LotR I have seen no dissent that Dain & Glorfindel are the best two heroes.
Dain's buff on top of the other dwarf synergies makes them capable of bulldozing most quests. Glorfindel has excellent stats that with Light of Valinor as a cheap Unexpected Courage that lets him quest & attack every turn (or defend if he is desparate). Since he has only 5 starting threat you get the benefits of 2 high value heroes for the cost of one of them.
These seem to be pretty much crutches for all of the top tier lists. So what are the best decks people use without using either of these heroes?
Either suggest a solo deck or use a pair of decks (or more) that can work together.