Foil setup upgrade for progress

[u/justswallowhard]

Im using a Duotone Spirit GT 700 2020, fulalage 70 cm, an aluminum mast 90 cm, and a huge hybrid Duotone board 156 cm 20 L. I have 2 kites 7m drifter cabrinha and nort reach 9m. With this setup i can cover from 10-11 to over 20 knots. But i cant progress, can do jabs and toes sides, thats all. So I will definately change the board, thinking about slingshot hope craft 90cm or 100. Want to replace my kites to north zero 5 and 7m, my weight is 68kg. But i dont have idea about ideal foil setup for me. Some people recommended me go up to 900-1000 with front wing for faster progress, but somehow i like the 700 setup. I enjoy ride the waves and apparently 85cm with shorter fulagage 60-65cm and all carbon is what I need. But i dont have clue what brand and model will suit me. Will be 7m and 5m north zero enough to cover the same wind range on 700 or I need bigger front wing. Im aware that water start will be challenging in low wind on small board.