I carry a smaller backback in the Denali 'Swoop' backpack and I think I am at my upper limits of weight capable by this backpack.

You really need to asses wether you would be able to carry a heavy BOB, and with the variables with what has happened for you to start using it and to lug it around with you.

Some of the items I carry in my BOB are the following.

-2 Sealed boxes of AA & AAA batteries (30pc per box - Lithium & Alkaline)
-Bug lotion in rub on 'Bushmans' - rub on is less wasteful and not a fire risk - it contains lots of deet (Australia sucks for insects!)
-full size duct tape
-Paracord & other ropes
-Micro Jimmy Bar
-LED Wand (multi function led)
-2 LED Torches - one for everyday and the other is for performance & light power.
-Chainsaw handsaw blade (self made)
-electrical cable and a button and spare LED's
-Thermal blankets
-Tarpaulin (3x2 meter)
-fishing line, hooks, swivels, wire trace etc (can work as a snare trap)
-good quality St/St padlock & keys
-Kong screw gate caribiners (24Nm), Kong belay & 15 meters of rope & a loop harness.
-Scrubbed / blacked out all the reflective pieces on my BOB for night time security (JIC).

And so many other things I cant remember off my head... I should make a list of it all...