The Homage: Jackson used some Elvish in his films, and the makers of The Hunt use subtitles when Aragorn and a fellow ranger speak their own language.
 
Lesson For del Toro: With more members of races such as the dwarves, we’re hoping del Toro brings his experience shooting movies that end up subtitled (like The Devil’s Backbone and Pan).

Don’t be afraid to use more native talk in the movie – it just heightens the experience.