I also found Bilbo's speech about helping the dwarfs find a home to be particularly moving because he doesn't have to do it. Frodo and Sam pretty much had to do their journey because they were saving the world. Bilbo doesn't but heads into danger anyway. Much more inspiring, I think.
Very good point. I quite liked that moment, too. Sandwiched between big action set-pieces, the film (and Bilbo) definitely needed to find (and explicitly express) a heart. As important as Bilbo's "heroic act" to save Thorin is, in terms of his character's growth, I think this scene was more significant.