IMO, the Moai are a bit underrated. You don't need to focus on a cultural, tall, VC to play Polynesia. Moai are perfectly good for border expansion in a wide empire. I think some people get tripped up as Polynesia because they spam the map with Moai and halt their growth. For most cities, building 3-4 Moai and only working the best 1 or 2 is a good strategy. Alternatively, some people try to overleverge the UI by settling in some ridiculously distant location, thereby losing 20 turns.