Comfort. That’s what it’s really all about. A few extra ounces ought not to be sacrificed to inadequate rest. That’s why we always carry our Cyclone Chairs (http://www.theultralighthiker.com/cyclone-chair/) @ 180 grams so we can really enjoy the time at the end of the day. We use Thermarest Neoair Xlite Women’s (http://www.theultralighthiker.com/new-hiking-mat-425g/) sleeping mats @ 340 grams and Exped UL Pillows @ 45 grams (http://www.theultralighthiker.com/exped-ultralight-pillow/)
It is important to always have enough clothes/adequate sleeping bags so you are toasty warm all night (without sweating, which will ruin the insulative ability of your clothes, bag etc). We have found the Montbell range lightweight and excellent (http://www.montbell.us/) such as their ‘Thermawrap series of coats and vests in synthetic and their ultra light down range such as the ‘Superior’ and ‘Ex Light’ eg http://www.montbell.us/products/disp.php?cat_id=2001&p_id=2301218&gen_cd=1 which can weigh as little as 156 grams. For sleeping I like their Ultralight Super Spiral Down Hugger #3 bag (@-1C & 595 grams) myself.
When the temperature drops below freezing I put a coat on the top half of my body and a vest on the lower half. This takes one down at least another 5-10C without carrying any extra weight. A warmer sleeping bag will also likely be too warm for usual camping conditions in Australia. When it gets really cold the bag has a draw string which can be pulled in so only your mouth and the bottom of your nose are poking out. NEVER breathe in your bag! I also own a pair of down sock such as these https://goosefeetgear.com/products/1-down-socks if my tootsies should feel the chill.
Of course we have a dry tent (such as this http://www.theultralighthiker.com/honey-i-shrank-the-tent/) and a warm fire out front, and of course two dogs for when it is a ‘two-dog night’!