The List so far (was coming to a conclusion)

[Lyn J. Mangiameli]

I'd add learning  more specific to Firenze. He has twice gone against the wishes of his kind 
(doing what is right, rather than easy), once saving Harry's life, the other "saving" 
Hogwarts. The latter resulted in his banishment from his own kind, and from the forest 
home he had known all his life. He also was very significantly interrupted in SS/PS as he 
was about to tell Harry more. I'd be most disappointed if we didn't learn more about both 
what Firenze knows, and what becomes of him.