My suggestion is quite simple, there isn’t enough information that may let players decide what style of gameplay pleases him more ( Skill simulator isn’t that good ).
To implement a Class Reset scroll at the store would cause a lot of problems to the game itself, to each new buff people would buy the scroll and get the best classes in the game.
Reaching lv 280 takes a lot of time and it is an achievement itself, for a casual player that makes a wrong choice , that would cause a lot of discomfort
To that reason my suggestion is : To every character that reaches lv 280 ( or in the future lv max ) gives him the right of 1 Class Reset Scroll.
