Gives and takes with everything but here are some more suggestions...
It looks like you are missing some odds and ends stuff but cant put my finger on it.
One for instance, You might want to consider a food bag of some sort like a Ursak minor etc.
You can save over 2# right off the bat with a different tent and pack but it will cost you about an extra $200. If you MYOG some stuff you can recover some of that but I would invest in a SUL top cuben tent and Pack from Zpacks if you really want to lose and extra 2 pounds plus.
A fosters pot is less durable until you put it inside a plastic Koolaid container and that container can handle boiling hot fluids, is absolutely crush proof and holds in enough heat you really dont need a cozy unless its really cold.
Also Holds your plasic bag when you eat, IE the bag of food goes inside the container and add water cap it. Adding that container works out to 3.8 total which is still lighter.
If you want to keep it lighter still then forget the plastic container and Without the container the top ring adds top rim strength or buy one of the machined rings and wrapping the works with a titanium wind screen would help keep it from getting crushed. These are so easy to make and cheap I look at them as disposable. A machined ring can be reused, so just buy a beer, drink it cut off the top and presto - new pot.
The stove I linked fires off in about 5 seconds and boils 1 cup of 60dF H20 in 4 minutes with 3/8 oz of alcohol. Now it depends on how much you cook and the temps, but for moving fast and say 6 cups of water a day, so about 6 oz weight of alcohol for 3 days. If you want to go lighter fuel then Esbit and add a small SS wire pot stand. If using DN alcohol, I do not want that container inside my cookware. Personal preference. Everclear is okay, but no DN alcohol in my pot for me.
There is a youtube of a guy with a sub 2 oz fosters cook kit you may want to look at for ideas. 2-3 days is not a big deal, and one of these is almost free to make and worth trying out just for the experience.
Why a double rainbow tent ?? A Zpacks Hexamid tent will cost about $20 more than the double rainbow and will save almost 2 pounds just by itself. If you are going double then you will split the weight of the rainbow. If you have some extra $ then get the larger hexamid. Tents are one of the really heavy bulky items. If I were starting over and a grounder, I would save and buy the lightest cuben tent I could afford. Zpacks hexamids are so light they are lighter than a sil tarp and bivy setup.
In the summer you dont need or want a 20dF quilt. Personally I have a MYOG modular setup and my 45dF quilt weighs 15 oz and thats for a tall. That would save weight in warmer weather.
A M50 Climasheild quilt like that cost about $90 to make depending although Tims equip is top shelf. I also have a 1.8 oz primaloft liner that weighs about 9 oz and a 5oz liner. The 5 oz liner alone is good to 30dF or so and weighs about 20 oz. Synthetics are bulkier than down.
The older Neoair smalls are on sale for about $90 and weigh 9 oz.
Use polycro (sliding glass door shrink film) for a ground cloth - $15 and 2oz.
Driducks are good. They now make a very thin poncho that weighs like 2.4 oz but not long enough for a pack. Just got a couple to try out and thinking about extended the back of one and adding some velcro but they are very very thin.
My normal driducks top weighs a little over 6 oz.
Jam 50 is too heavy. I have an older Jam II that the bladder sleeve is stripped out it weighs right at 18oz. Bought it used for $50 here. Personally doing it now I would save a little more $ and just do a one time lay out for a Zpacks Arc-Blast.
You can go only tablets for water if you want to go lighter although I like the sawyer filters but you will most likely want to replace the squeeze bag. From what I have read the bag will blow out and some have gone PDQ. Personally I made a little system.
2 plastic bottles cut in half, some tubing, prefilter and adapters. Use the bottom to scoop, top of the bottle as a funnel fastened to the filter with a tornado cap or arrowhead eq cap to tubing etc. something of that sort, and just gravity filter.
FYI look up IceAxe here, at least I think that is his name here if I recall correctly.
He did an AT thru with a 9# pack and you might get some ideas from his post here.
Also check out this guys setup. He is a hammocker but he only has a 20L pack, 9# pack total weight and did an AT thru with that gear. That might also give you some ideas. He has a series of around 125 or so videos of his walk and they are interesting
His gear is pretty close to my setup now, but I did a MYOG double layer 1.1 oz hammock, Climashield topquilt, 1.1 oz sil tarp and I carry a MYOG 10 oz bug net. Also my setup is a lot longer than his, IE my hammock is 12' long where he carried a 7 oz nano hammock.
I probably have about $1000 into everything and have no cuben.
Next on the list is definately an Arc-Blast pack and that wont save me any weigh but will give me more space in my pack.