As I have been playing this game over the years, I'd just like to point out that the game seems to be quite ...hmm.. "exact", what I mean by this is that we need a variety within classes. Twinking is an element that can be used to differ from others but as a whole, Bears are Bears and Birds are Birds(don't get me wrong).
My suggestion is to add scrolls, as I have gotten this idea from the Pocket Legend like game, Maplestory, (Koreans dominate this game LAWLZ) this means that there is an amount of times you can scroll an item, scrolling an item will increase its stats by a certain amount. Items that have been scrolled more often compared to others can be sold for higher prices which leads to diversity within each class, PVP, and PVE. Skill stats will vary and will take more strategy, also taking in to account that if this is implemented, there would be many problems that will arise. Noting crazy inflation will arise.....
Just putting something up for thoughts
P.S. If you guys wanna try out Maplestory here is the link, http://maplestory.nexon.net/