Do not expect the same performance using Wine compared with Windows. Wine as you probably know is used to emulate all layers necessary to run Windows applications, it will never be the same as you have in a Windows system.
For increasing the FPS I would suggest running all your gaming sessions under Unity2D, that is important because you do not have the composite desktop taking part of your graphics card performance.
For World of Warcraft as you said changing from D3D to OpenGL helps in most cases bit in the end you will have to eventually lower the graphic details options to run the game.
Try a lower resolution, decrease the graphic details a bit and them some more until you are happy with the performance.
When I played World of Warcraft on my Ubuntu system I noticed 2 things always: lag and ping to server was much better and graphics quality always had to be much lower than the one I used in Windows.