I'm not at all a specialist of speed as I do less than you
but if the goal is to break your own record with your equipment, you have no choice than sailing down wind:
- First, you need to adapt/reduce your V and shim properly your stab to navigate cross and down wind confortably. Of course, it is going to be a bit more difficult to take off in normal conditions (more back foot). But with higher speed, the foil will feel more balanced.
- Then the stance, you need to be in a low stance with a higher boom (lower gravity centre), in this "frog" position far from your sail ... so very long boots (40'') are necessary to avoid this feeling of being catapulted.
- if you struggle with the sail, I usually twist my waist forward and put my front hand closer to the mast to let the sail open when I feel over powered. Not sure if it's a good technique, but it works for me in strong gust. If it's still too much, well .. you need to reduce the sail.
I think with these steps, you will know the limit of each of your front wings. For instance, I think I have reach the limit of my freeride wing (1100), it saturates at 21-22kts, I didn't manage to do more. With the 800 wing, I'm around 24-25knt but it's not over yet ... I feel it can do more but now it's a problem of skills