For light and warm packable, I really like KUIU. Full disclosure, yes, they are a sponsor here, but this is the stuff I wear personally.

I have their superdown hoody which goes in the backpack. It weighs nothing, and when you get to your glassing spot, out it comes. It's warm, breaks wind, and fits me great. Also carry a KUIU rain shell. With these two I am warm and dry. Perfect for the backpack.

Hard to beat their superlight carbon fiber packs too.

Put on gear like this, use it a few times, and then put on the Cabelas or BassPro heavy duty stuff, and it's like night and day.

"What we obtain too cheap, we esteem too lightly: it is dearness only that gives every thing its value. Heaven knows how to put a proper price upon its goods; and it would be strange indeed if so celestial an article as freedom should not be highly rated." Thomas Paine