Oh man I can think of so many.
1. General overview of how sets were designed and finalized.
2. What were some of his ideas that never made it into the game?
3. What sets did he work on?
4. What are things he would have changed in hindsight?
5. How did they make them?
6. Does he recall any sets/plans or potential directions Wizkids had in the works? Like what was the direction they had planned for the game?
7. Favorite memories of Pirates and his experience?
8. Ask him about his current projects and let him have some time to talk about his career now.