I need the ability to carry 80-90lbs a few miles in my pack without having to hunch forward 20 degrees. I've tried the Eberlestock J34(Too heavy, can't handle big loads), KUIU Ultralight(Too light to make a good shooting platform, doesn't carry heavy load well), and Eberlestock X1E(can't carry load over 50lbs well).
I'd like a pack that weights no more than 5-6lbs. Enough compartments to keep a full sized spotter and med sized tripod separate and ideally covered(dust free), and ideally 2-3 separate compartments other than a main bag. Could live with a ~+/-3000 Cubic Inch main bag, if I can strap tent/meat outside. Most important is ability to carry a 3 day camp and meat tight against me, where I'm not fighting the weight hanging back or the pack slipping down. Lastly, I can't have buckles regularly breaking when synching down. I carry rifles that vary between 8.5 and 12.0 lbs all in including ammo, so while I don't expect the Eberlestock type carrier, I need a reasonable system as I Won't, just sling over my shoulder on one side.
I'm not shy about spending money on a good product.