Rain gear used on a boat, ie. foul weather gear, is not the same grain gear I would wear hiking the AT. Nor would I wear the same gear on a motorcycle. What I have used on the AT: Marmot Precip, similar to the Golite Virga, and earlier Golite rain gear. DriDucks work, but tear easily, but all of these are designed to be worn while hiking, not standing still in torrential rains, monsoon, flying salt spray or wind driven rain riding a cycle.
As for hiking shirtless, yes, that can be done on the AT on a warm rainy August day in Vermont, but would send you into hypothermia in September rains on the side of Katahdin.
Another piece of rain gear perfect for an AT through hike is the Packa. It is silnylon, not breathable, but it has underarm vents and a front zipper. It has a waterproof zipper down the front. It is low enough to keep shorts dry. Which means it does well to keep you warm on a chilly evening while at camp. If you are not wearing a pack, the packa will cover your butt . It serves as a raincover for your pack and it is a cover that does not have an opening between your neck and the pack. It can be taken on or off without having to remove your pack. It folds into its own pocket when stored. It was designed by a guy, trailname Cedar Tree, who lives in Marion, VA only a few miles from the AT. So, almost half way through your hike you could meet him! Silnylon will tear, so, be careful if sliding down on your butt over steep granite. (Sometimes that is the best way to get down a trail section of the AT)
Over the long haul on the AT The lightweight WB rain gear will eventually wear out at the shoulders where it chaffes under your shoulder straps. The coating eventually wears off. Hopefully, this will not happen during your hike since most days will be dry with your raingear stowed in your pack.
Gortex jackets with nylon liners would be nice to have in the winter months of your hike, ie. March in GA, NC if you are hiking north. But, spring and summer rains, the lighter weight jackets are fine.
I use Reed pants with a zipper which I sewed into the legs as someone had suggested at BPL. Marmot Precip Pants are fine, too. I have worn them to bed, too, for warmth.