I've been using a Lafuma Cordillera 60 pack for weekend hiking trips. It's a 3600 cu. in. pack, with a separate bottom zipped area for a sleeping bag. The pack has a built in rain cover, and compression straps around each side, wrapping around a couple of full length pockets. It comes in a couple colors I think, mine is what they call graphite, it's 2 tone. I bought mine from a local dealer, but, it's available at several places online, here's an example I found online with a picture and specs:
http://www.sportsbasement.com/jump.jsp?itemType=PRODUCT&iProductID=6078This is a modified panel loader pack. The dual zip front goes all the way to the top, where you have an extended waterproof collar that can be pulled closed with a drawstring. The cover, with zipped storage space, goes over that. There are loops on the pack to strap your ice axe and shovel. There's a sleeve inside the main pack for a hydration bladder, and a Vecro flap for the tube to be routed to one of your shoulder straps.
The waist belt, I think, is very comfortable, even on the second day, when I usually find my hips groaning.
It's not big enough for longer trips, unless you travel ultralight. I also find that in winter, I sometimes need to use a larger pack for the bulk of extra clothes, more stove fuel, a 4 season tent, etc. Still, for most of the trips I took over the past year on weekends with the Scouts, this was the pack I used.