I think most people I go out with are rocking that size. Some no larger than you. They do cinch up quite a bit. Of course for slackcountry riding I would carry something much smaller. I know going out for a day in backcountry, I can't carry what I need to have. Sure I have some items that most people don't want. In addition to the standard avy package, I carry a first aid kit, SAM splint, CPR Mask, a warm layer (micro puffy), extra gloves, extra goggles, plus my food and water. All of that is stuff that I don't always or rarely use, but when you need it, you are awfully glad to have it. Pretty hard to get all of that in a 20 liter pack. Plus skins are going in the pack on the down and they do take up a fair amount of space. Of course those can go in a jacket pocket if it's big enough.