I'd like to offer empatheias as a possibility. It's a sol/adventure based game where characters arrive on a floating island where emotions are the driving force. There's also the opportunity to explore the wider world as well, and try to figure out what happened to it. I believe it fits most of your preferences, though it probably leans more towards medium pacing wise, but is very backtag friendly.

I currently play North there and would love to see Carolina.