I'm about 75kg (in summer anyhow

) and would usually use a 6.6m KA Koncept in the winds 15-20 and a 5.8m Koncept in 20-25 knots.
The 6.6m Koncept works best on the 460 mast (same mast as my 7.5m Koncept) but a 6.6m KA Koyote (no cam freerace) works best on a 430 mast and has great performance. Might be worth considering?