It’s a rare bit of gear that doesn’t suffer some modifications. Here’s what I’ve done to my Exped Thunder 70 pack.
1) Shoulder strap daisy chain. I used quite thin (10mm) grosgrain so I can attach lightweight items to one shoulder strap if I want.
To ensure the loops are securely attached, the top seam is sewn to the zip backing. Logically it would be better to have horizontal loops rather than vertical but they might tear the fabric of the pocket.
All quite simple, but adds to the utility of the Thunder.