One major change I would predict in Pern society is a trend to more equality of gender. Racial troubles are effectively non-existent. Prejudice born out of differing lifestyles was common, but few serious problems developed. As the Weyrs become more self-sufficient, I see these problems diminishing even more.
The male-dominated Feudal style society grew out of hard times, just as it did on ancient Earth. I believe that in little time, women will begin to assert themselves and move into areas of responsibility that before were male dominated. I expect many more females will become dragonriders, master craft persons and even lord holders. The increased demand for teachers would create opportunities for women in the Harpercraft. The image and role of the dragonriders in Pern society would change. They would no longer be the heroes of Pern, but would remain an elite group. As the Weyrs became more independent, old animosities between holder and riders would diminish. The weyrfolk and the dragons would become protectors and provide valuable services for the rest of the population. As technology begins to advance, more of the population of Pern would require higher education. The Harperhall would expand, and schools
would begin to open in all holds. Fewer people would be willing to work as drudges, and fewer of that class of worker would be needed.