this is good for a few beers and as many hours .
Having been thru this a number of times -here is my take on it.
in the size stuf we fly and having done that size and 40% and 33% and 27% etc., ----
what really counts is simply good solid but very light structure
Then make that as thin as practical
then just make a nicely rounded leading edge and keep the trailing edge a bit thick -to keep it stiff.
As far as making it snap better or causing problems
no problem with kinda sharp or blunt but thinner airfoils are more efficient for this type model.
The wing loading and correct balance and throws make far more difference.
Th old bit about snappin Caps stemmed from the ungodly heavy Caps mostly 20L types kitted by various mfgrs
Keep you wing loading for the 35% at under 35 oz ft -but preferably lower (as close to 30-32 as you can get) and you can drag it in .
the pics are a 40% I designed for some local friends - these weighed 36 lbs -with tuned full length pipes ZDZ160 and DA150 with in cowl mufflers- absolute rockets.
The wings are clipped 9% from scale the rest of the model is scale.