Really? How many people do you know who are called Settler?
I'd like to see something change when you assign a settler to a role. Perhaps the settler doing a supply route gets called Caravaneer, the bartender becomes Bartender, and so on. Perhaps different clothes or hats for each role. There have been more than a few occasions when I have allocated what I thought was a free settler to a Scavenging Station or something, only to then find a store unattended.
I'd also like to see something that lets me see which supply route a particular settler is on, so I don't end up reassigning the wrong one (which I've also done a few times).
There are a few named settlers, like Blake Abernathy, but most of them are just called Settler, apart from the ones called Worker (The Slog, I think).
You can guess which ones are running your supply route, however - if find a character named Settler in the wasteland with a laden brahmin behind them, they are a supplier.