Herlock,
I am going to quote your post in order to make some comments but don't take me wrong, they are not directed to you strictly!
Hi. I always wear 3 layers of tech clothing when seriously

hiking; an inner layer is a short/long sleeved polyester shirt in contact with the skin, second layer is a polyester fleece/pile with a wind stopper membrane and the outer layer is a Gore-Tex shell with thermo-sealed stitching. I remove or add the layers based on the conditions
Layering is still THE choice for dressing outdoors but you have to be very careful choosing them and deciding what to wear. Even in subzero temps, if you are heavy loaded, moving fast/over difficult terrain or both... if it is NOT windy... a long sleeve base layer could suffice. If it is windy, put on a windrpoof shell, but forget about a third layer between the two, because you will be sweating like a pig and overheating
I have to say that I usually avoid going out in the rain. It is not funny or enjoyable (for me) to be wet the whole day. If it just happens, I try to keep warm (and sweaty) and keep as many layering clothes absolutly dry inside plastic bags in order to have something to change into when I am back to a dry place.
That's why I love winter... snow seeds easily and provided it is cold enough, you don't get wet and don't need watherproof clothes (stretchy softshells are all you need, the colder, the better).
....and trail running shoes with Gore-Tex membrane.
If you are wearing low shoes (not boots), chances are you will drown your feet once you step in the wrong muddy puddle. You could choose to wear gaiters, but wearing them in the rain requires to put them UNDER the pants, so the wather running down the pants don't go inside your gaiters and then your shoes (for snow is the other way arround, you wear the gaiter OUTSIDE the pants). Usuallly if getting wet is unavoidable, shoes without membrane are ligther and dry faster!
Again in winter you don't have those issues! LOL
I also use a water-proof back-pack cover..
I don't like pack covers because they add weight. Unnecesary weight if the backpack is made of a waterproof fabric! It doesn't need to have a watertight submersible closure on top (rolled), as long as the top closes well enough, you are set.
I also dislike ponchos. If it is slightly windy, they end up flapping all over the place. And they don't let you see your feet! It gets interesting when scrambling through rocks...
Keep in mind that I don't do much recreative hiking camping... but mostly climbing (either rock, ice or alpine) and my "hiking" consists on approach hikes to the huts or to the climbs themselves!