easy & quick access to locks.
a retaining strap so the bag doesn't slip while cycling, but allows you to swing it around to your front for easy access when stopped.
some sort of lights?
include a charger for phone etc... as couriers don't have access to a socket on the road (solar, kinetic, dynamo etc.)
reflective materials - the tweed run organisers had a small amount of relective thread woven into their gear so that even though it looks like tweed - it has subtle reflective qualities in the dark
easy & quick access to locks.
a retaining strap so the bag doesn't slip while cycling, but allows you to swing it around to your front for easy access when stopped.
some sort of lights?
include a charger for phone etc... as couriers don't have access to a socket on the road (solar, kinetic, dynamo etc.)
reflective materials - the tweed run organisers had a small amount of relective thread woven into their gear so that even though it looks like tweed - it has subtle reflective qualities in the dark