Id judge a kids character much more on how you see him act in practice, games, and speak to him in person. And by the recommendations of his coaches and other people that have contact with him. Not twitter.
Ive had teammates drafted in the teens. The scouts have a ton of direct contact with the players. Before and after games, during practice, phone conversations. Watching his actions during practice.
You get a much better indication of a kid's character in those interactions than you do by something he says to his friends on twitter.