I LOVE my Helios 55. Love, love, love, it. It just seems to “fit” on my body. I would echo about wanting some attachment loops along each side of the front stretch pocket. This would allow the owner to put their own cordage on it. Also, if I’m being really picky, I would change the way the hipbelt tightens. Instead of pulling towards your back, I would switch it to the way most companies are going in which you pull forward.
I am thru hiking the AT and interestingly, at the last minute (like 2 days before), I decided to go with another pack I’ve had for a while. Why would I not take a backpack that I absolutely adore? It didn’t fit my system (the way I pack my tent, store gear, etc). Since I decided on a different tent than what I was using with my Helios, it changed the way I pack and my other pack met my needs. On the bright side, I’ll be shifting to a tarp style shelter over the warmer months and will have my Helios shipped to me. I miss that girl but you gotta go with what makes everything work.
Long story short, I love Katabatic Gear (also have the Flex 30). The Helios is a tremendous backpack with regards to fit and load carrying abilities.

