Great advice Alan, but after 40 years you probably know the answer to the last, while the OP may not.
Your 19kg pack weight would be 2/3 food (+fuel)
Food for 2 weeks would be about 5.5 kilos. I use gas not white fuel these days. My stove weighs 84 grams and for a long trip I take 1 full 230gm gas cylinder plus a half size one. My tent is just over a kg, sleeping bag just under. Heaviest item is my Macpac Torre rucksack which is 3kg but I refuse to take an ultralight pack. Macpacs are simply indestructable. Other than one pair of socks, jocks and lightweight shorts I carry no spare clothes. Best way to dry wet clothes is to wear them (generally one layer at a time).......Having said that I am not considered an ultralighist by their fraternity. They sleep under tarp shelters, blah, blah, etc. etc. and look down on anyone who doesn't do it their way. I avoid them like the plague as all they want to talk about is gear. Fortunately they don't usually venture where I do. On my last trip with a Leica (my M6ttl) some years ago I drowned it in a river in New Zealand and my wife wont let me take the ME (that was a condition of buying it.)
I think that puts things a little more in persepective, thanks Alan.
I'm no ultralight camper, but it has influenced my approach. And yours, I see.
The main thing, IMHO, is to be confident that every gram is there for a reason that will satisfy me when the inevitable fatigue + aches set in. Your MacPac bag would be an example. I personally would use either the lighter pack of the list above, or a 1.4kg more rugged (and older) one. You are satisfied with your pack and happy to live with any weight compromise. You won't sit down after three days and go "I wish I'd brought the 500g ultralight spiderweb instead."