What are the motifs in Arrow's Flight by Mercedes Lackey?

A key element of this novel is magic, and Talia's primary dilemma concerns her Gift and learning to control it. The world of Velgarth is plagued by Sorcerous Wars, and the kingdom of Valdemar emerges, complete with the magical aspects of Companions and their Chosen. After Talamir is murdered, Rolan Chooses Talia to become the Queen's Own, and Elspeth is overjoyed when she is Chosen by Gwena.