Suppose it depends on the big three: time of year, location, conditions. I typically take too much clothing in summer, never knowing what the overnight temperature might be--shirtsleeves or blowing sleet? Sometimes after pulling into camp I can't throw on every stitch fast enough and sometimes I reluctantly put on a windshirt and hat to ward off bugs, despite sweating like a sumo.

We've all had that sinking feeling of putting on the final stitch of clothing and still being cold. I hate that, so have decided for any trip longer than a weekend to pack one "luxury" warm item--a down vest or jacket--in case the weather takes a wacky turn or I run my "batteries" too low on the trail and need the warmth before dinner revives me. Most trips it's overkill and is just a (welcome) pillow, but I have it should I need it. (Down gear has become incredibly light and compact the last few years.) My main clothes are preferences I've formed over the years and ease my life in picking clothes for the trip, organizing and packing them, retrieving them in camp and packing the next morning.

Most of my in-camp needs are handled by a wicking short-sleeve tshirt, a mid-layer zip-t, an insulating layer, a hooded windshirt, a knit cap, wicking boxers, dry socks and long pants. Spring to fall, this is good for 80% of my needs. I might want shorts in mid season, rain gear for the wet or a headnet for bugs, and I have my backup "pillow" just because. If I get home having not used the rain gear, bug net and down top, that's a "win."

One concept I've tried and rejected is hybrid jackets with removable liners. Neat idea but as executed, heavy, bulky and not as good as carefully selected separates. The "wearable" sleeping bag still intrigues me, though.

I probably didn't address your point directly. Until fleece became lighter and more compressible I seldom carried it--at least not the thicker stuff. But for consistently soggy conditions, it's still one of the best options, along with wool and synthetic fill. Finally, I haven't a clue whether the new treated down garments changes the landscape yet again. Sounds too good to be true.

p.s. anytime I'm headed for 10+k feet I make sure to have a safety margin. Living in a hot place at sea level, I don't always respond well two miles up, and it can be especially hard to stay warm.