Without a doubt ... school #2. The first "offer" is not an offer.
The P5 school has not even offered yet. They may continue to string him along. If they are already pointing out his flaws during the recruitment phase (dating process) then I can't imagine them falling in love with him? I don't see this ending well.
A very wise coach told me... You get yourself better in college. Go where the coaches love you and you'll play. If are good enough, you will have a chance to continue on to the next level. Better to be with a coach that believes in you and will give you the opportunities to get on the mound and develop.
As far as what to say to a 16 year old? Present it to him in a different analogy...... If he was trying to choose a date for Prom...
1st girl reluctantly said she would go, but you really aren't a couple, and if anyone else shows up at Prom that she likes better, she will ditch you.
2nd girl like you and has already said yes. She's excited and wants to tell all her friends.
3rd girl is most popular in school. Everyone wants to take her. She keeps telling you she may say yes, but at the same time tells you that you aren't really popular enough, or good looking enough...but come hang out with me and 14 other guys and let me think it over some more. I'll let you know.