My advice is to accept that you will need more than one kite. Small medium and large for the different winds.
People riding mountain boards tend to end up growing into depower foils.
I suggest you get a quality 3m 4 line fixed bridle. Learn to fly it without looking at it at all + hooked in. This will become your high wind kite
once you master it. By then you will have a better idea how big a depower will suite your typical winds.
Kites: 2.5m Profoil , Quadrifoil XL kitesurfer, NPW 5 Danger.
Flexifoil: 1.7m Sting, 4.9m Blade 3, 9m Blade 2.
Flysurfer : 19m Speed 2 SA, 7m Pulse
Peter Lynn :18m Phantom, 15m Synergy, 10m Synergy, 1200 Farc, 460 Sarc, 130 Tarc, 5m Peel, 4.2m , 6.4, 8.5 C-Quads, 3.5 LS2 single skin.
Rides: Flexi / P.L. Frankin'Buggy , Shaped + straight skiis, sand skis, Coyote blades. Core 95 ATB. RKB R2 ATB .
Ken (K2)