John Stevens is 16 years old. I would expect him to develop over the next 5-10 years, but he is not AI material just yet (and maybe never will be). He is quite limited in his style of singing and didn't do well at all on the nights he had to sing outside of his comfort zone.
That being said, I like his style, but I'm coming up on 58 and this show is targeting a much younger audience. A lot of this has to do with personal taste. I play in a 20-piece Jazz and Swing band and our female vocalist has sung back-up with Barry Manilow and has done a lot of commercial work, but my wife doesn't care for her singing. Like I said, personal taste.
John Stevens has to find his niche and he is young enough that he has plenty of time for that. He just isn't an American Idol. My vote goes to Fantasia, Latoya, or Jennifer in a three-way tie!