The only reason things turn OP in this game, is because there are no diminishing returns on anything. You can stack pretty much every stat and there is no penalty for doing so, you can splash multiple primary attributes (Str/Int for example) and be effective in multiple disciplines, while still without any diminishing returns or a penalty for this splash.
Not that I am really complaining, but this is the core of the problem. Gear is not that overpowered, it is the mechanics behind all stats that make every sensible build overpowered, and crafting makes it too easy to get all the stats you want.
