Please read the articles on the home page of this site that I linked for you, most of which are about gear selection. Check the websites for the "cottage" manufacturers that I mentioned. It's with those "cottage" manufacturers selling on the internet that the true innovations in backpacking gear are taking place, not at REI, that bastion of heavy "traditional" gear. The ones I listed are all reputable firms.

Just for comparison, here's my "Big 4": Pack, from Six Moon Designs, 29 oz.; tent, from Gossamer Gear, 27 oz.; 20* sleeping bag, Western Mountaineering, 25 oz., pad, a 3.5" thick R5 insulated air pad from Kooka Bay, 13 oz. All except the sleeping bag) are from the "cottage" manufacturers. All of them are extremely comfortable--they have to be because I'm an old lady with arthritis and a tricky back. My total "Big 4" weight is the same as your pack alone.

There are many, many brands of packs besides Gregory and Osprey. You should be able to find a comfortable pack that weighs far less than the Baltoro. You certainly shouldn't need a pack that weighs more than 3-4 lbs. Did you try any of the packs from Granite Gear? Deuter? The REI Flash? One "cottage" manufacturer you definitely should check out is ULA-Equipment.com. Do remember that the pack really should not be purchased until after you've acquired your other gear. The pack not only needs to fit you but also needs to fit your gear (neither too big nor too small) and support its weight.

Please read those articles and look at some lightweight gear lists before you purchase any more gear! Here's a gear list with a lot of alternatives from a gear dealer who lives close to my home. Several of the regulars on this forum, such as balzaccom and phat, have links to their gear lists. You can find many others by googling, but I suggest you not try to emulate the ultralight (under 10 lbs. base weight) category until you've had a lot of experience.