If Peter Pan's advice cannot inspire Clark to fly, I don't know who could.
Is "Twisting the Hellmouth" Buffy-lore? That would be scarey to have Clark grow up in that universe, where everything which is born with powers would be considered evil. (Even if his invulnerable skin / fast healing powers and super strength could be said to be Slayer-ish, he is male and therefore odd to have such traits.)