A world this size would likely have to come in an EP. The original RH had over 90 lots, obviously we wouldn't get that many but I would want a 4-6 apartment buildings with several apartments in each plus several(5+) lots along the Boardwalk area including several large lots to accommodate the rides and carnival items.
The game could be expanded on with the addition of a new festival lot type that could be placed in any world and have rotating elements of the rides and carnival foods appear and disappear week to week. Similar to the sims 3 seasons festival lots.
Plus cars, obviously a major selling point.
All the carnival foods could come in the form of food stands or food trucks.
Loving the midway games ideas
Maybe this could add surfing, they did surf in the 1930s