Strengths:

1. Can use mail as armor at level 40. 
2. Can use a shield while a hunter cannot. 
3. Can heal.
4. The best combo for a spell caster/fighter. 
5. Can self-rez and then resurrect the rest of the group.

Weaknesses:

1. Totems need to be managed constantly.
2. Due to the great flexibility of the class, its hard to focus on just 2 or 3 attributes. 
3. Can not use weapons like swords and 2 handed axes.
4. Can dual wield only if going deep in the Enhancement tree.