reefwarriors.wordpress.com/2018/08/07/naish-lift-foil-sail-review/
I did a little write up on my fav Foil sail if anyone is interested.
Really interesting to know. Didn't realise how much more practical the lift sail is. Have learned with regular wave sails, but can now see what you're saying wrt bottom end power and the lack of top end.
Personally I see the waves as the best area windfoiling will expand into.
The ability to cruise the out back swells and the challenge of going deeper into the wave zone.
I am using GOFOIL's , they are the best in the waves and for WWF (Windsurf Wave Foiling). I use the IWA wing for big waves and the Maliko 200 for small waves/light wind.