When Im backpacking, I always have my daybag on my front, which normally has my camera wrapped up inside a microfleece inside.
If it's cold and Im wearing my microfleece, then the camera is in my daybag loose.
Bear in mind it is all watertight as there is a drybag inside my daybag and backpack.
I wouldnt bring the grip.
Re charger, batteries, filters etc, I normally put that sort of thing in what I call a "Tupperware Oyster," or one of these
things. Unfortunately my own isnt hello kitty. Which I then throw into my main pack, its solid so I can put fragile things (filters) inside and again watertight, but again that doesnt matter as my whole bag is in a drybag.
Best of luck with your travels, take lots of shots!