Ah I see your point. TBH any bag is going to get pretty hefty with the kit you want to take.I have an expedition 7 with my current kit in and I have problems even lifting it up, as I have problems with my arms. It's difficult to imagine which bag would do, I will have a good look around at focus, but I need some ideas of which ones before I go.
Tamrac Expidition 6 user here too.
They are fab bags but heavy when loaded up!
For day trips I use a smaller Tamrac (3375 aero speedpack 75) and it got me round Canada just fine!