Starting at level 1 feels completely out of place with the characters being introduced...
It's true they're all grown adults with backstories, but I don't have a problem hand-waving the starting level at 1 as this being their first real "Adventure" in D&D terms. It's the adventuring that drives the level-ups, and none of the companions/Origin characters in this game have ever faced this kind of thing before. Something like that.
It's better than some of the other tropes that game designers use to start players at level 1, like the tired "amnesia" bit, or a farm boy venturing out of his village for the first time.
