Sorry, but I'm voting no.
This would/could punish people that don't deserve this.
Sometimes games last too long, and you just WANT TO leave.
Sometimes people get invited for a party, and guess what's funnier? Playing solo in team games, or playing in a party in team games?
Sometimes your internet just lets you down...
And sometimes you just have to go because your parents need you, you had an appointment...
Most of these are just innocent, and if you were to punish them so they can't play team games for 15 minutes, you ruined their fun if they went to a party, log back on in 3 mins after their wifi is back...
This would just ruin people their experience on the network...
That's why I'm voting no.
I've always said that instead of punishing the ones who left, you should reward those that stayed.
Maybe give them the teammates their items?
Not something they didn't have, because this would get abused.