Another Animal Crossing idea. If you have a friend come over to your town and they have a pwp in their town that you do not, they should be able to go to the town hall to tell Isabelle about it. That way you could build it once they’ve gone home and you don’t have to wait on animal villagers to suggest something.
Something like this is what I mentioned a while back would be nice. Another version of it was if you saw a Public Work in someone else’s town, you could give bells to Isabelle to unlock it and have the option to build it.