I hope that MC goes all over the planet be it Secret Places, Pocket Dimensions, Incredible Master Individuals (like BRUCE WAYNE did but more extreme) to be a person with the "TRAIT: MASTER OF ALL"
Kamara Taj would be the best plastic due to their ability for the Mirror Dimension. His ability is highly destructive and the Mirror Dimension would be a good training ground and way to separate fights from the real world.
Most Fanfics show the MC enjoying his freedom and not liking joining an organization, and like almost all the protagonists have this trait, it looks like ctrl c ctrl v to me.