I have found the weight and space comes from Ice axe, crampons, stove and sleeping bag. 2 pound down sleeping bags are not that expensive these day, under $200 and they pack down really small. Ice axe could get spendy but you could pick up a light weight axe for under $100, the crampons get spendy if you want light. I have chosen to go with the new Air tech super light, they are more like $150 and up. Stoves, well it really depends on what kind of meal you want to eat. My stove weights less than 3 pounds with the fuel.
A great tip for breakfast is put granola in a zip lock and place powdered milk and dried fruit in the bag. Bring a light weight bowl and spoon which will double for other meals. Each morning pour out the granola and dried milk into bowl. All cold milk and walla you have a hearty breakfast that will last in you for most of the morning. Works like a charm.
Hope this helps
bone