As you said he is young and that is the one thing that will change at some time and it is hard to know if or how that change will effect him. He is young and hungry now but eventually he will grow up and probably want to get married and have kids and no one knows how soon that will be and if it will effect him or not.
I have seen so many different crew guys and race car drivers change dramatically when they get married and even more when they have kids...it can change their whole out look on what they were doing before. I'm not even going to try to guess how many wins he will get...I'm just going to enjoy his racing adventure while it's here. But, I hope he is still racing even if it is in a wheel chair when he is 100 and still racking up wins.