I have played this and I will say it is very fun! And I don't usually gravitate towards "empty world free roam" games! Really great job!
However, I have noticed a few "technical issues" and have a few suggestions for the game, should you continue to work on it.
(This is just how I would customize the current state of the game for myself and is in no way trying to put you down or criticize you or the game.)
In the order that I have come across each "issue":
1. Issue/Suggestion- Option for remapping game controllers. (With my Logitech G F310 gamepad I can't look around while sprinting and the B button pauses the game. Also, there is no button to dive with the gamepad. I tried using a third-party remapping software and it didn't do anything.)
2. Issue- The first-person camera and third-person camera can face different directions. (e.g. First-person can face south while third-person faces north causing character to turn around when you change the view and are moving forward.) Probably what I would do about this is make it so that when entering first-person mode the third-person camera matches the first-person camera angle relative to the character. I haven't used Unity so I don't know how it would work in there, but I understand the logic needed to do this. (EDIT 1 MONTH LATER: I just realized it's probably not that simple. I also found the FAQ in the game files since. Is it possible to make Cinemachine cameras children of each other? If so could it work to make the 3rd-person a child of the 1st-person and then rotate the 1st-person whether 3rd-person is active or not? Or something like that?)
3. Suggestion- Maybe a way to swim faster under water.
4. Suggestion- Also the whales are kinda slow compared to the original so I would speed them up a bit.
Like many others I would also like to see vehicles, custom Miis, NPCs and such.
Again, this is just what I PERSONALLY would change about the current state of the game.
I won't say "Nintendo needs to" but I do think it would be cool if they offered to license this game making it an official Wuhu Island free-roam.
Once more, really great job! Keep up the good work! :)
P.S. I just realized this has been updated 5 DAYS AGO! I will try the new version and say which of my "issues" still stand. :)