Smotyndu

I use an F-Stop Harney pouch ($75) - it holds a X-pro2 with 16mm plus a spare 12mm zeiss/23mm or 56mm - and has enough room in the main bag to hold my (very) lightweight Montane Featherlite jacket; in the front compartments I can get two spare batteries and a Think-Tank SD Card wallet. When not being used as a shoulder back it is home to my 100-400mm zoom and 1.4 teleconverter. It has a detachable shoulder strap and also has MOLLe fitting so you can attach it the hip-belt of an F-Stop backpack (though I usually have a smaller Redfern pouch attached to hold my Lee Filters)

Probably the 10-24 - mainly due to lack of weatherproofing. So when I'm out walking I either use the 16-55 or if I want to go lightweight I use the FujiFilm 16mm (often with either a 12mm Zeiss or a 23mm FujiFilm just in case)