I agree, buy Ryan Jordan's book. If nothing more, it is inspirational and really changed the way I thought about things. Check our Ray Jardine's stuff too. In the end, clear your mind of conventional backpacking principals and all the stuff mass marketing has put in your head. You can have the same gear and remain safe, you'll just do it lighter.
As you'll figure out quickly, lightening up is terribly freeing, but it requires you to make very specific gear choices and you really need to focus on everything. Let me repeat - EVERYTHING.
The Osprey is a great pack, but you can go lighter. Check out Granite Gear, ULA-Equipment, Gossamer Gear, etc....and keep in mind that you likely can get a much smaller pack then you think because most of your gear will be lighter and smaller.
Your sleeping bag isn't too bad in weight, but much like with everything, you can go lighter. You can buy quilts from this site, Jacks R Better, and several other places. If you want to stick with a bag, I'd go with the Western Mountaineering Highlite which runs slightly over a pound and many people on this site will tell you it is a tremendous bag. If you don't think a 35 degree 850 down bag will be enough, wear some extra clothing instead of investing in a heavier bag which won't have as many uses.
I looked into hammocks too and spent a ton of time and money trying to find one that worked. In the end, I didn't find them comfortable, they had no real place to store anything, and other options were lighter and offered more space. You could get a tarp (Gossamer Gear SwinnTwinn is my favorite) or a tent of all shapes and sizes. Henry Shire's Tarp Tent is popular on this site, but I chose the Six Moon Design's Lunar Duo because it offers my tall frame more length.
You mentioned condensation. Well, you'll get condensation in nearly everything, even a tarp. One of the quickest ways to mitigate condensation is to get something waterproof and breathable. Check out the bivy's sold on this site which will keep your bag drier then without it for just a few ounces.
If I can suggest one thing, it's LOOK before you buy. Study gear lists from others on this site, ask a ton of questions and you'll learn that there are a lot of options out there. The people on this site are invaluable to the lightweight backpacking community and each offers amazing insight, skill, experience and study to even the most mundane topic. My biggest mistake was buying before I fully appreciated this market because I was blinded by the fact that there was more then just mainstream marketers of backpacking equipment. The reality is, the "good lightweight stuff" is offered by small shops who don't offer their products to large vendors such as REI, EMS, Dick's, LL Bean, Cabelas, etc. Many are represented on this site. Basically, do you homework, ask for suggestions, weigh EVERYTHING as you'll be suprised how quickly a few ounces can add up when you discard their value for several items. After you knock out the big three (shelter, sleep system, and pack), you'll need to focus on lightening your other stuff (stove, clothing, water bottles, pad, etc.).