By comparison, Tahani getting coffee for demons and forever working behind the scenes rather than as the party hostess was humbling herself in a way that revealed that personal growth.

Yes! Like you, I would have liked to see her get more to do throughout the season, but at least we know that in the true Good Place, she really shines.

Chidi's calendar and Michael getting to be a human were great moments, too, I agree. And I hadn't thought of connecting Michael becoming human to Jeff getting a real frog, that's really interesting! It was also a very kind gesture for Michael to make as he was leaving the afterlife and embarking on humanity.