I've been primarily hiking with an Osprey Talon 44 the last two seasons, carrying reasonably similar loads to yours. I just like this pack (and I have a boatload to choose from). It has enough capacity for up to about five days and is really comfortable--for me. It's one of very few packs I've owned that doesn't create sore spots at my hip and shoulder bones after a long day, or several long days.
It's relatively light and relatively cheap, but definitely not featherweight. If you can find one to demo, I'll recommend giving it a close look.
I hear ya. I sure don't want to go to any heavier pack than I need. I think the size/shape thing along with essentially un-padded hip and shoulder straps pretty well sums it up. I think the ability to adjust torso length, etc. will be very helpful in my case (along with a bit more padding).
My present set up for the "big four" is around 8 lbs for bag, pack, sleeping pad and tent. Where I run into trouble is with the weight of all of the other stuff I seem to think I need:)
I appreciate everyone's feedback so far. The Trek has been a pretty comfortable pack up until this year. Things just must change as we get older. I don't know how many years I have left to backpack so am not interested in tying a lot of money up in a pack. I will look into the ULA packs.