While I have somewhat clear ideas about what elves, dwarves (coming soon), and humans are like in Weyland, my ideas on halflings are a bit less solid. On one hand, I was thinking that they were mostly slaves/servants to the Elves of Cadiz. Professional servants, almost -- permanent squires, butlers, and the like. On the other, I want the races to generally conform to the race descriptions in the 5E basic rules. And no one really wants to play a race that is perpetually second class.
So I am thinking halflings may be an island people, initially conquered by the Elves of Cadiz when they came to this part of the world. But the halflings revolted, the elves moved on, and now they are mostly free (and carefree) folk. Some have "chosen" to remain servants of the elves, but just as many now live and work autonomously. Those in Weyland may be settlers, former elvish servants, or merchants.
How's this sound?