BlueBarrel/Gear; Hard to really get everything you want into 1 60L barrel. Either eliminate some stuff or plan on an extra drybag of gear too. Also try not putting stuff into gear bags so you can smash gear down together more compact. Leave the gear bags on top under the lid so you can sort stuff as you unpack it.

BlueBarrel/Food; The reusable canvas shopping bags work good for me when I'm using the barrel for food. Seems that what you want is always on the bottom. Plus the bags keep stuff organized. I know opposite of the gear idea, but the food is always going right back in each time. Gear gets unpacked once and repacked once, food is always getting sorted though.

BlueBarrel/Flying; Don't forget the small plastic tiewrap under the lid seal. Otherwise you'll you find your barrel sucked flat from the air pressure change at the baggage pick-up.