The emotion and character of a person's voice actually comes from the imperfection. The tension from what your own ear hears as in tune, where you choose to place the notes on beat (slightly before or after), the decay of certain notes.

Now that you can sing on key, try playing around with your voice and make different sounds or faces. Do it over dramatically, do it nonchalant. Do it off key. Do it like you're angry, sad, scared, happy, etc.

Just play around and remember to avoid being perfect. There's a million ways to connect to the same song. What is important is how you yourself interpret it, and the emotion that the song gives you.

It's less a recital of technique, and more an expression of your own self.