Queen Morgase Trakand is a "good" character who makes bad choices and gets humbled somewhat during the storyline. I wanted an actress who was the right age to have a child as old as Elayne but who didn't look middle-aged, and I think I found her in Frances O'Connor (right). She's 45 but looks ten years younger. Her coloring is also appropriate. She's a recognizable face (she's on Mr. Selfridge at the moment) but won't be required to be in every episode, so she can balance the two.
Another fan favorite is Elyas Machera, former Aes Sedai Warder turned wild Wolfbrother. He's described as "older" but I always pictured him looking kind of "wolfish" himself, and I wanted an actor that could portray that look. I'm not familiar with the work of David Sterne (right), but I like his look.
Finally, based on the fact that Rodel Ituralde apparently becomes an important character in the last three books, I decided to cast him, despite the fact that in the books I've read he doesn't do much. Juan Chioran looks appropriate, but honestly I kinda blanked on this one.
Next Up: The Aiel!