I really enjoyed the nostalgia this game gave me. I loved the game and how accurate it is as I remember, as I've always dreamt with a game where you can free roam Wuhu Island.
I know it's a practically new game, but for next updates I'd recomend the option of having an automatic running button, the ability to ride boats, cars, bikes or another type of transport, and other mii's in the island (like NPC's)
Maybe this is too much, but the option to make custom Mii's or having the ability to get Mii's from 3ds or Wii? and maybe you could see other people Mii's roaming in the island