How has the dynamic between the three protagonists (Luke, Leia, and Han) changed since the original Star Wars movie trilogy? How does that affect Timothy Zahn’s narrative?

How does Thrawn compare to Darth Vader or the Emperor as an antagonist/villain? Cite specific examples from the text to support your argument.

How do the politics of Heir to the Empire affect, maintain, or change the adventure-story tone that the original movie trilogy set?