I find the closer I get to finishing something, the slower I work.
Anyway, I had said there would be "Good Realistic End" and "Good Unrealistic End". This is the Unrealistic one, but I looked back and decided to cancel the Realistic one because I felt it was too boring. So this is simply "Good End" now.
In the Realistic one, Finn says the same thing, but the Cosmic Owl simply agrees and sends him back up to the mirror where he fell in. He encounters Ice King again there, tells him that while he may not have known what IK has gone through, he believes that there's a kindness in him that's been walled away in fear of getting hurt, but joy cannot be found without having first gone through pain. Says that anything of value is worth striving for, walks out of the place, leaving IK kinda stunned/humbled there.
But I felt that was a bit too forced-moral-lesson, and scrapped it.