DryDucks are fine and confortable, but I find them very "rubbery" and fragile so I have made cagoule-type rain gear out of silnylon remnants that weight less than 6 oz, come down under my knees, is wide enough to accommodate a small pack and be reasonably ventilated. I can tuck my legs underneath and be totally protected, when seated...Love that, resting and waiting till the rain stops !
It's something between a poncho and a normal jacket, packs very small, but I have to be careful in forest or bushes. Anyway the "slickness" of silnylon avoids a lot of snagging...Design comes from a "larger than large" Kinsman pullover pattern, with a hood.
Quite easy, if you have silnylon leftovers and a sewing machine...