I personally have made three languages so far, but don't think its necessary. Its an immense amount of work that is completely useless, since you will not be writing your book in that language, at least if you want others to read it
As long as you know the basic functions and other items, its good. As Ravana said, make sure it has some basis in fact and try visualizing it yourself. Although, you could try doing the opposite for comedic effect.
Very interesting, I like it a lot.
Agreed with Chilari, its not a common way to portray things in fantasy.
But a fresh outlook is usually the best when it comes to this sort of thing. Good job :)
Naga is a good race. Also, google is your best friend when it comes to this sort of thing.
However, I have to fundamentally disagree with you on this one. Elves are my favorite. Half the fun is finding a way that people haven't used yet.