I'm struggling to see how a lot of old features/characters will be incorporated into this game. I'll list some out,
1. Dr. Shrunk
2. Museum
3. GracieGrace
4. Mayor
5. The Nook/Nookling stores, you can see the Nooklings in Tom's craft store in the trailer.
6. ANYTHING else that was on main street.
Nintendo has only done that in apps as far as I know.I hate games where it takes a few hours to get your item
if they actually end up delaying, a march/april release next year
Maybe it will be the opposite of New Leaf where you'll have to get on Kapp'n's boat in order to get to the mainland and Main Street instead of the island.