Those look to be nice pants and exactly what is needed for hunting out here. Regarding wool- my experience is the better and thinner wools do not "get heavy" when wet. They simply expand to a small degree, tightening the weave of the fabric which essentially forms a barrier against more absorption.
Perhaps when compared to fabrics like those in the Attack pant, wool would then be regarded as heavy. I have also tried wool pants that were too heavy, even dry. Cheaper wools, woven poorly, are never a good option.
I would love to see an Attack pant in very light, tight woven wool. I'd buy that product in a heartbeat.
Joshua