Impossible without cash and you know it. By the time someone legit farmed feathers and got them to +18 without any abradants we'd all be dead from old age. The only people who might have done it for free were the same ones that got mass banned for rohanopoly abuse.
So in other words no, you can't name an MMORPG that puts less effort towards skill/class balance then Rohan. I don't know why you even mentioned Tera when they put way more effort into tweaking skills and game balance then Rohan ever has lol.