Luffy's charm really helps sell this game, with the open world being quite beautiful at times. But some issues with the combat, lack of Straw Hats interacting with the world, and the lock on system being a pain during some fights gives this enough flaws that some folks might not be able to ignore.
Mulaka has some promise, but some issues in certain areas. It has a really cool soundtrack, lovely atmosphere, and the hand drawn style of the graphics makes it stand out. Sadly, some of the mechanics just bring it down a bit. Perhaps with some future updates some of this can be fixed, but at least the foundations of the game are solid, and the story is genuinely interesting.