Have you seen the FireWire Deviant fin? Great for upwind and tightens up your turns. Here's the description and you will find it available on our Buy a board now section of the website.
The DEVIANT automatically adjusts 7° of cant in either direction (14 degrees total range of movement) increasing speed & responsiveness by reducing rail-to-rail drag & shortening the turn radius: your board will feel faster, looser & improve upwind performance. Throughout our testing we felt the benefits of the automatically canted rear tri fin immediately