I dont know of a perfect combo, but for me, natural fibers and breathability win out every time. Before I really knew about wool, I hated putting pul on dd, and usually ended up packing some doublers in her diapers and going coverless. Yes, even when we were out and about and in the car. I just imagined myself wearing pul over my underwear, and how uncomfortable that would be. Now I know with newborns it really is one of the best options for bf poo, and I will have some nb pul covers, but I will try to mostly stick with fitteds and wool.