BWD is correct, the stab decreases the overall lift a tad on normal foils.
Kami, you are correct, "wing loading" is essential.
The numbers on me are wrong though, but doesnt matter for the principle really.
I am 78 kg (meaning average weight which is 75 to 80 kg), and ride wings from 520 to 1200 cm2, and dont have any Moses foils.
Wing loading is essential if you are foilsurfing.
When kitefoiling it is partly essential yes, you are right.
But only partly and not proportional, because when heavier you use a bigger kite, thus not needed a similar bigger sized wing.
It is the same as for twintips, if you weigh 50 % more, you use a bigger board, but not 50 % bigger in area, as your kite lifts more.
Also, there is a tradeoff in terms of agility.
Meaning, at some point the heavier riders prefer a tad smaller board than the "relative" difference, for being able to toss it around fast and fun.
So yes, the "wing loading" is essential for which size used, apart from personal preferences.
I like that the wing is low drag and I can foil fast without any kite power.
Others ride with bigger wings and are more powered, thus they use the kite to ride faster.
Two very different styles... I like that the wing itself rides fast, without having any kitepull.
My wing loading for the "overall" wing 790 cm2 is around 100 g/cm2.
For my big surf wing it is 65 g/cm2.
And this is the size I feel can become boring, it you dont have any waves.