For complete waterproofing for the least weight and bulk, nothing beats the Mica (women's version is the Crystalline). It delivered on a three-day Adirondack soaking that ended with testers wringing out their socks. It's made with Marmot's MemBrain Strata, a ripstop nylon laminated to a polyurethane membrane with a silky inner coating that keeps it from feeling clammy. The translucent fabric looks delicate, but it held up well to normal wear and tear on several multiday trips. Downsides: Breathability is fine for moderate trail hiking, but not for steep, sweaty climbs; the DWR wet out (but the fabric didn't leak) in prolonged rainstorms; and the low pockets aren't hipbelt friendly.
$130; 6.5 oz. (men's M); men's S-XL, women's XS-XL; marmot.com.