Backup QB is mostly a salary cap issue and doesn't need attention at this point. Unless you want to pay 7 Mil and say goodbye to any hopes of resigning OBJ this position won't change unless Stafford gets hurt and is out for the Season.
If Akers were to go down I could see adding fringe type starter as we did last year but the cost for that is not going to be to high.
Defensive Backfield we just have to figure out who is ready to play the best. Plenty of backups
Offensive Line: Again we have good backup but need to figure out who is the best person to start. Looking ahead this is a position we will need to add to.
Edge: This may be a position where the backups may be lacking but we have enough guys going into training camp to evaluate if our backups are ready to step up and play. At least 1 of them will need to be in the rotation. At really good replacement won't be cheap.
Punter: Again this is more about which guy is ready to go out and win the job.
Potentially I could see some issues with backups but nothing that screams out that must be taken care of before training camp.