The club have already stated they have plans for KB so no worries, I hope he continues to develop the kids as he has done in the past.
Bally should be allowed to grow within the new coaching set up. Three or four years time he could be ready if needed.
I reckon he should be put in charge with ensuring the Sunderland's footballing philosophy is followed throughout the squads, from under 18s to seniors. The reason Barca is so successful is having a setup that allows the youth team to adapt very quickly to the senior squad as they play the same way and use the same tactics. minor differences in set up allowed between the coaches, but the general philosophy should be the same. Ball has always tried to set up to attack, and play fast football. Even though we lost at Man U and liverpool, I liked the way Ball was trying to get the players to play. Under 21 squad is always scoring bags of goals as well.
Bally should be part of the first team as well as the youths. He would be a great coach and no one would be slacking on his watch. He could gain valuable first team experience too.