Could we all be missing something? It might help if you gave us a description of a typical trip, and what makes up the 50 pounds you're going to be putting in it. For example, a 7-day trip might consist of one day hiking in, setting up a camp, doing something out of that camp (hunting, dayhiking, etc.) - or it might consist of 7 high-mileage days. In either case, the pack recommendation might be different but, more important, we may be able to help reduce the 50 pounds to 25 or 30. (You say you're just getting back into this - after how long an absence? Gear has changed a lot, mostly for the better, over the last 10 years.)

Also, when you say "frameless," are you referring to a pack with no frame whatsoever (like a duffle bag with shoulder straps) or are you simply referring to a pack that doesn't have the old aluminum-pipe external frame - which would mean you want recommendations for a pack with an internal frame (not what most of us here consider "frameless.")