Most of us around here are looking for a down bag that weights 1.5lbs or less! For sure, that weight of bag compresses down and it don't take much toom. Like the poster said you can have any two things, I choose warm and light! Still, you can occasionally find a good bag for $200-300 if you watch out.

Have to agree that your backpack and your bag are the two pivotal gear choices, starting with your bag. There are not many good choices for good bags, less than 10 in my opinion, that fit the warm and light criteria of 1.5lbs and 30F. Luckily there are many backpack and tent choices so you can make those choices in bag, backpack and tent order. Least then you can't buy too much tent if you buy a tiny backpack!