- You have two sleeping bags listed, a 20deg and a 0deg--- are you expecting to be closer to one temp or the other or even colder that you are looking to double bag?
-If you are looking at cold temps below 20degF then I would look for additional ground insulation; your BA Insulated Aircore will not suffice without another CCF pad under it or you could upgrade to something like an Exped 7.
-Forget an alcohol stove in winter also. Switch to white gas, yes the stoves are bulkier and heavier but they are tried and tested and unlike alcohol they will actually work in those single digit temperatures.
-Filter, forget about it sub-freezing temps-- water will freeze and crack the filter. Chlorine tablets and boiling are much more efficient and reliable for long-term winter use.
-Your clothing is also lacking for those zero degree temps-- a good down parka and pants would go a long way or at least a heavier baselayer like Cap 3, Cap4 or even R1.
-I don't see any gloves in your list-- you will want liners and an overmitt at the very least. I use OR PL 400 and the BD Mercury mitt, the latter will probably be overkill above 5deg-- but good glove practice is essential in the winter.
-If you expect snow, look at gaiters to keep the snow from getting into your footwear and wetting out your socks. Being wet in the winter can cut a trip very short.
-I also advise against bladders with a hose in the winter-- they freeze. A good nalgene with a cozy/sleeve works much better when your water freezes easily.
-If you are expecting artic winds/blowing snow then try to cover as much of your exposed skin as possible-- think balaclava over hat, ski goggles over glasses etc.
-Dri ducks-- probably great for 3-season use, but poor in winter for keeping out those winds. Look for a good hardshell in wet conditions or a good softshell in dry conditions. For the former you could look at Goodwill or Arc and find suitable 3-layer Gortex jackets that will hold up for a season or 2.
-Winter also for me equals snow-- so I automatically think microspikes, crampons, snowshoes and ice axe. Not sure if you need this on your trail, but it is worth finding out before you go.