This one has been a mainstay in my load order for quite some time as well. What I will say is that, at least on its own, it's less a "random chance to be courier" and more "is the courier," however it's still a pretty cute replacement.
To add to this, this also pairs quite well with Courier Delivers to NPCs. With both mods active, you can see your little Alfiq courier friend showing up regularly in towns in order to give deliveries to various NPCs! Definitely helps liven things up a bit while playing.