The glassing approach “I” would use for stringerless is a symmetrical schedule. However, for me, I like symmetrical on any type of board ( surf, skate, skim, etc.)
If, I am forced to do my own glassing on my stringerless 5’6” EPS Coanda Channel board I will do 6/4 top and 6/4 bottom.
I agree with Gene and a professional snowboard builder on this.