Hi Matagi,
I did the Overland Track with a 25 December Christmas Day departure, and my LighterPack list that I took is here:
https://www.lighterpack.com/r/bz0cqfAfter I finished the hike, I did a review and noted:
#1 - The fingerless sun gloves I took were INVALUABLE and everyone was envying sun gloves. The reason being that the sun was beating down and those who had sunscreen on their hands found that the trekking pole strap fasteners which went over there hand were abrading the sunscreen off. Everyone had blistered sunburnt hands. I can't recommend the sun gloves highly enough.
#2 - The Leukotape I took was also INVALUABLE and I would take twice as much. It was so helpful for dealing with any blister or strapping up foot. I am a convert and prefer it over sticking plasters and anything else. One can wrap a large length all the way around the foot in a circle even several times so it doesn't come off and stays put.
#3 - The Aegismax Down Hat which was bought on Aliexpress and weighs 70 grams added so much warmth at night if it turned super-cold, and I'd recommend that option to anyone going into potentially really cold weather. During my hike there was only one really cold night when it got down to -2 and it was great on that night.
Now going through your list, my thoughts are:
- The Aarn system is quite heavy at basically 2kg, and you could shed close to 1 kg by going for a different pack (Like a Hyperlite Mountain Gear pack, or a ULA Circuit (68L), or Sierra Designs Flex Capacitor, or Osprey Eja, etc) However if you love the Aarn system or don't want to spend more money then fair enough.
- I high recommend a wide mat and I totally think it's worth the extra weight so that your arms don't fall off the side of the mat and I get a much better night's sleep for the wide size mat. I'd suggest that you try it out before you go or ideally before you buy to check you do like style and feel of it, but looks good option to me and R value of 3.7 is pretty good. (Options that will provide higher insulation are things like Thermarest XTherm but I believe these are more expensive in Australia then the Sea to Summit Comfort Light.)
Clothing
- You could save 250 grams by ditching Crocs and instead taking some hotel slippers bought on Aliexpress, which did the job fine in my case.
- Camp & sleeping clothes - I highly advise an 800 fill Drydown puffie jacket with a hood, which should weigh around 260 grams; a polar fleece with hood which should weigh around 240 grams, and a set of the thicker 220 merino pants and top which should weigh around 350 grams combined.
- Extra base layer - I recommend base layer thickness merino short sleeve top and leggings which should weigh around 220 grams combined. (And you can alter these out for camp clothes / sleeping clothes if weather is too hot on any night for the thicker weight merino.)
That set-up gave me flexibility to adapt to cold weather at camp, or indeed hot weather some nights when I just slept in base layer merino. And the polar fleece was precious because I could hike out in that on cold morning and take it off and stuff it in pack when it warmed up.
Camp chair
- I would ditch and just take a Thermarest Z-Seat as a sit pad (or sit pad made of 3 segments of Zlite Sol).
https://www.snowys.com.au/extra-warm-z-seatNow I would add by way of context I have a Helinox Zero which I seriously considered taking and have taken on hikes before. I ended up not taking it and I didn't need it at all. The reason a chair wasn't needed and wouldn't have been appreciated by me was that the huts all had benches to sit on, and there were sit spots on route or logs to chuck my Zlite Sol sections. There wasn't a single time I wished I had taken my chair.
And that section of Thermarest Z-Seat was great to take out to put pack on to protect pack from mud, or use for organisation outside tent, and a variety of purposes.
Everyone who knew what they were doing in generality had one of the Zseats or had made one from sections of Zlite or had bought another generic brand from Aliexpress that is essentially same thing.
But overall pack set up looks great and I wish you all the best trip in the world.
Best,
Emma