90 villagers is your max population (well actually you could get 91 or 92 if you get twins or triplets). You cannot build anymore huts at this point. From what I've read in other posts, the "worried about housing" is a glich that will be fixed in updates.
Once every puzzle is solved, you're done the game. Time to start a new one since they're all different is many ways. Try playing on harder levels! I kept my first game going though when I started new ones and check in on my original villagers from time to time to see how they are coping on their own. Quite well actually!
There are rumors around this post that the hints you've found may be clues to sequels. Other than that, they really don't mean much for this game (unless you get an island event).
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My VV2 story, "A Twist of Fate" And don't miss Krystal's stories, all three of them!
"Life is too fast... unless you're in traffic."