ok. My character is blind and unable to speak. im so horrible to her so i gotta give her something, so i give her the inapt ability to smell and hear things better than most people. good trade off yes? ;P
As long as you don't exaggerate it wildly. While it is realistic to have increased other senses, it isn't so much so to hear through walls 50 feet away lol. Just remember you aren't daredevil :P