I really wish Bethesda would go more towards giving my character a voice. It is amazing to me that with all the voice acting, thousands of hours, that every single character in the game has a voice but YOU!
I really loved the Gothic games were my character would speak.
In OB when my Argonian got hit he'd go "Ohhhgh" in a human voice. That always seemed very wrong. Hope they fix it for Skyrim.
On a side note, that would nearly double the amount of recorded dialogue, as your character would have to respond to most of what is said to him.
Even worse than that - if done right they would have to do a different voice for every race. 10x the voice acting!