Simon,
The point you make about the leeward wing acting aainst the righting moments is true unless it folds up. An additional consideraion is the windward hull is closer to the pivot on winged boat and this needs to be taken into account when dimensioning the wings. For the specific example I was using it amounts to the wing being 100mm longer. I have not done the numbers for a Tornado because the hulls are heavier than 30kg but it would be more like 150mm wider ie. 750mm wings on 2.5m wide platform to get the same outcome.
I would not consider wings unless they folded up and
the windage can be minimised in their design.

Regards,
Phill

I know that the voices in my head aint real,
but they have some pretty good ideas.
There is no such thing as a quick fix and I've never had free lunch!