Jason Momoa is the second actor to play a DC Comics hero (Aquaman) and a sentient snowman; the first was Michael Keaton, who played Batman in the Tim Burton films and later appeared in Jack Frost (1998).
This is the second film produced by Geoff Johns that is not a comic book adaptation. The first film was Lethal Weapon 4 (1998) (but he was uncredited).
At a height of 6'4", Jason Momoa is the tallest actor to voice Frosty the Snowman. John Goodman, who voiced Frosty in Frosty Returns (1992) is 6'1". Jackie Vernon, who voiced Frosty in the animated Rankin/Bass TV special, Frosty the Snowman (1969), was around 5'4" (1.63 m)