Most Efficient way to carry this list of things
Eberlestock X3 lo drag. Stow the rifle in the scabbard. Put a carabiner on your rear bag and clip it to the MOLLE webbing on the exterior of the pack to save interior space. Carry your pistol mag out in a good holster. HSGI double decker taco...
Hearing Protection
I had a pair of these made, SPL variant. Expensive maybe, but they're comfortable all day long in your ears.
https://www.1964ears.com/product/SPL-Plugs