This is a somewhat controversial subject, so keep in mind that this is just my opinion, and I might change my mind any day now.
- Conflict of Honors
- Agent of Change
- Carpe Diem
- Plan B
- I Dare
- Local Custom
- Scout's Progress
- Mouse and Dragon
- Ghost Ship
That's the main weave. I have not yet figured out exactly where in the sequence it is best to read Crystal Soldier
and Crystal Dragon
for the first time. There are advantages to having read them prior to reading Plan B, but that does rather disrupt the main flow of the narrative. Reading them after I Dare or Local Custom would probably work, too.
For that matter, if you're a romance fan you might want to pull Local Custom to the front of the list, then do the rest in the order shown. If you're a military SF fan, you might want to try Agent of Change before Conflict of Honors.
Balance of Trade
poses problems similar to Crystal Soldier and Crystal Dragon. It provides nice background for some events in those two books and in Saltation, but it isn't really essential to have read it anywhere in the series.
(These problems didn't exist when we were all waiting with bated breath for the next novel, and happy to get any new Liaden material. It is only the ability to sit down and read the whole story-so-far without interruption that creates dilemmas.)