Appearance Customization is good but it sometimes can get a little too much and becomes more of a distraction. The dressing up in Pokemon X&Y was nice but they definitely could have worked more on other things (the plot)
However, personality customization is one of my favorite things in games. The fact that certain choices depict how your game will end is very interesting to me and a major thing I love about Reborn and also Undertale.
It makes the game worth being played multiple times, unlike a game with 1 story line and 0 options.
Breaking the fourth wall is very funny to me in most instances, but also can be used in a very serious tone (Undertale). It all depends on what YOU want to do with YOUR creation. is it something you want to be funny and classic? Or original and edgy? however you want your game to be is the best way to decide where to put these factors
hope it goes well