This 25 liter example from the Less Is More series is full of smart detail.
Airback carrying system with great airflow
bluesign certified 70D*140D diamond ripstop polyamide
Side stretch pockets
Hip belt pockets
Space and ports for a hydration bladder and hose (not included)
Front panel elastic for overpacking and compression
The hip belt is wide and well padded
The bottles and hydration bags shown in some images are not included in the price.