Ah, W_D, I'm so glad to find someone else who has the same approach to rain gear! I too have given up on "breathable" fabrics which, at least for me, are not breathable. The exception is Frogg Toggs, which IMHO are too easily damaged and are not wind resistant enough for really cold, windy conditions. I have a silnylon rain jacket and pants (made by Brawny Gear, now out of business) which is extremely light (7.6 oz. for jacket and pants together). Once I sealed the seams, there was no leakage after 45 minutes in the shower, nor have I noticed any leakage in the field since. Anti-Gravity Gear makes
a similar silnylon rain jacket, with a full-length zipper and therefore more ventilation. I haven't seen any silnylon rain pants recently, though.
When I'm hiking in warm and wet conditions, I am soon in a lather when wearing a rain jacket, breathable or not. I therefore leave off the rain gear, wear just my supplex nylon hiking shirt and pants and get wet. If it's not quite so warm but still warm enough that I'll sweat in the rain jacket, I wear a lightweight wind shirt. I put on the rain jacket when I stop to avoid evaporative cooling, but the jacket comes off when I start hiking again. If the rain stops, my body heat dries my lightweight supplex clothing in 10 minutes or less while I'm moving.
In cold rain, especially when the wind is blowing, I've found no difference between breathable and non-breathable shells--when it's cold the breathability seems to make no difference either. I wear just my normal hiking shirt and pants under the rain gear. If it's a little too cold for that while I'm moving, I may wear a lightweight insulation layer (such as a lightweight fleece vest) under the rain jacket. If it's really cold I may add a headband for my ears and thin gloves under rain mitts. My main purpose is not to sweat while I'm moving, but of course I don't want to get chilled, either. As soon as I stop to rest, I put on my insulating jacket under the rain jacket; if it's cold I'll add my heavy fleece gloves and balaclava. In blustery winter conditions, I might be wearing my base layer under all, but it has to be extremely nasty for me to need to wear my base layer while hiking. Outside of bug season, I wear a very lightweight wicking base layer top instead of a supplex shirt.
When I camp for the night, my tent (carried in an outside pocket of my pack) goes up first. I then take my pack (kept mostly dry with a very lightweight pack cover) inside. Of course my wet rain gear and wet pack cover come off in the vestibule as I go inside. I undress, get into my dry and warm base layer and re-dress (leaving off my hiking shirt and pants if they're wet) before the circulation I've worked up from hiking slows down too much. If it's cold, I wear most or all of my insulating clothing. I then unpack my backpack, get out my sleeping bag and blow up my insulated air pad. Anything I'm going to need outside is placed right next to the door. I grab water containers, gravity filter and the Ursack containing my food, put my rain gear back on and go outside. I tie the Ursack to a tree and head for the water source. Upon returning, I boil water and start my dinner rehydrating, feed the dog while I sip hot tea, take him for his post-prandial "stroll" and bury his leavings. The dog chores take up just the right amount of time for my dinner to rehydrate in its cozy, so the next step is eating.
If it's still raining, I brush my teeth, do any other chores, secure my Ursack for the night and head for the tent with the dog. I dry him off as best I can in the vestibule and put on his lightweight fleece jacket to protect my sleeping bag from his wet fur. If the rain has stopped, the dog and I usually go for a sunset walk before bedtime. If it's really cold, I've learned that a brisk walk or vigorous calisthenics for 15-20 minutes at bedtime get my circulation/body heat revved up before I get into the sleeping bag and make it easier to warm the bag.
If my hiking clothing is wet, I seal it (and my wet socks) in a plastic bag and put it inside my sleeping bag. That way the clothes are at least warm in the morning. I usually stay in my base layer (with insulation if neccessary and rain gear on top) while I eat breakfast and feed the dog. I then change into my hiking clothes (left in the sleeping bag so they're still fairly warm) and pack everything up while I'm inside the tent. My tent is the last item to be packed whether or not it's raining in the morning. If it's raining, my pack contents stay dry; if it's not raining my tent has the maximum time to dry out. The tent goes into one of the outside side pockets of my pack, where it doesn't transfer moisture to my pack contents and is available without opening the pack if it's raining when I make camp that evening.
Unless the visibility is too low for safe hiking, I'd far rather keep hiking than spend a whole day cooped up in my tent. So would my dog! With careful attention to keeping all my insulating clothing and sleeping bag dry, appropriate layering to avoid sweating when moving or getting chilled when stopped, and using fabrics that don't absorb water, I am a lot more comfortable hiking in nasty weather than sitting around.
If there are what our Pacific NW forecasters call "sunbreaks" during the day, I stop and get out my tent, sleeping bag and wet socks to dry as much as they can.