While interesting and convincingly executed, it's also in Terelle's adventure that we get to see the problem of brevity. Essentially, while long, this book either needed to be two shorter but more-fleshed out novels, or to make cuts. The departure from Khromatis has been built up as almost impossible, but seems relatively simple when it occurs. Furthermore, a lot of discoveries simply aren't followed up from! We get tantalising clues about new relationships between nations, new discoveries about magic, etc... But it's impossible to see where they go.
Luckily, the one plotline that doesn't fail in this regard is Kaneth's. The Reduners were some of the more interesting characters in the previous books, and Exile puts them back where they belong: high-powered, intrigue-rich excitement. It's a fun and unpredictable conflict, and definitely brings the novel out of its slower moments, though it does lack for a more thorough explanation of Kaneth's new powers as 'Uthardim'.
The ending to this series definitely isn't unsatisfactory, however - it's simply a lack of deeper exploration in terms of consequences that fans of worldbuilding may regret. Nevertheless, it's an engaging, fast-paced read with some rich history - and every one of the previous novels' characters get their turn to play a role in the climax. If you've been enjoying the Stormlord books so far, this is a must-read: just don't expect it to go much deeper.