[Xanthe]

Local Custom was the first one I read, IIRC, simply because I'd seen a mention that the authors were fans of Georgette Heyer, whose books I love. I can definitely see her influence in the way Liaden society and manners are structured.

I think that Local Custom is a good intro to the series because it gives a nice sense of Liaden cultural attitudes, which makes the behaviors much more explicable in context. I think you get a better appreciation for its nuances, so that in later books when someone tries to play melan'ti tricks with Korval you can understand how egregious the behavior is.