Ok here's an idea for the 'character' tab button, which has always been grayed out.

Your character portrait starts out plain. Using duel points since all of us has tons of unused points, we can buy items to equip our character. Each item has 10 types of quality and designated by color. The beginning item would be white (using a karate belt as an example) and the most expensive of that particular item would be black, which would take lots of dual points to buy. These items are permanent boosts. For instance, buying a white pouch would increase gold gained by 1% while having a black pouch would gain you 10% from every mission that gives you money. Other equipped items like a gun belt would reduce the health refill timer by 1 second, or a vest would add an additional X points to whatever your defense points are currently at.

As players equip their characters, an all black equipped character would imply a completely maxed out character.

just a thought to spend duel points.

-G

Also, a 5 day marathon event to kill all the world bosses as you can would be great idea as well.