"To The Sky" is an uplifting heartwarmer, especially if you've read Guardians of Ga'Hoole (but even if you haven't).
Speaking of heartwarming, Taylor Swift's song "Enchanted" is a sweet song about meeting Adam and being, well, enchanted. The Valentine's Day after it was released, Adam posted his own version of the song on his blog, directed to her. The heartwarming is pretty well summed up by his tweet about it: "Dear Taylor, everything about you is beautiful. I want you to know I was enchanted to meet you too."
An example from All Things Bright and Beautiful, Honey and the Bee is a pretty sweet song. Kudos to Adam for setting up these two lonely individuals and then bursting into possibly one of his sweetest, most beautiful songs yet.
These lyrics from Plant Life:
If I were to pluck on your heartstrings, would you strum on mine?
The whole of Vanilla Twilight is naturally one, but the last verse in particular:
And I'll forget the world that I knew, but I swear I won't forget you/Oh, if my voice could reach back through the past, I'd whisper in your ear/Oh, darling I wish you were here.
Tip of the Iceberg may have one set of creepy lyrics, but it is honestly sweet and heartwarming. From the Determinator narrator braving the ice and snow, to the final set of lyrics, which are honestly just beautiful:
snow drifts build up and enfold us/as we wait out this winter storm/so we snuggle close in the darkness/and keep each other so warm...
Dreams And Disasters is an upbeat, catchy, and great song about not giving up through the good and bad times.
"Peppermint Winter." He manages to capture everything we love about Christmas, and set it to a beautiful melody.
This peppermint winter is so sugar-sweet, I don't need to taste to believe, what's December without Christmas Eve?
This set of lyrics from Gold are remarkably touching.
I don't need the stars in the night, I found my treasure, all I need is you by my side, so shine forever.
'Cause we're burning bright, as we all unite, and when it's all said and done, we'll shine like the sun, so don't let the fire die. And we'll watch the sky, as it fills with light, and though the embers are new, whatever you do, just don't let the fire die.