I've heard that swimming around for a while helps trigger a ping, especially if you're trying to get one from someone in particular. I guess they're just programmed to happen every so many minutes? Be sure to fill your inventory with flowers so you limit the types of pings you get.
In my experience with new towns,you need to have the 100% approval rating and the Development Permit before your villagers can move.Oh,you probably know that you have to pay the down payment on your house too.You should also speak to all of your villagers at least once so you'll get the ping when they're ready to move.