Thank you!
Mechanically, I'd make populated islands the same way, but the 3 features would also have a social dimension (e.g. a Focus could be a person, a Path could be someone showing you around (what do they show and not show you?), and an Impression could be an observation about the society/traditions/etc.). (e: though obviously sometimes people don't wanna be found, as happened on Anastrophe Island and Redemption Island)
I've been doing mostly uninhabited islands partly because I started out in the same mental space as in the playtest version (where you explore "monuments" in a post-apocalyptic wasteland) and partly because one of the inspirations for this is the Pocket Atlas of Remote Islands, which includes a lot of unsettled, barely-inhabited, or abandoned islands.
Good points about open-endedness and the passage of time. For open-endedness, the subjective PoV and almost-guaranteed incompleteness are meant to help leave untied threads! I'm interested in which ones you saw as more or less open-ended—some I can guess at, but with others I dunno how much a reader might see as settled vs open to interpretation.