1. Right Tackle: Though this position may not even be addressed, I think it is still their biggest need. Indy signed Gosder Cherilus to a big deal to be their right tackle, but he is honestly one of the worst tackles in the NFL. I consider him quality depth at best. The Colts will quickly find this out when Andrew Luck is constantly getting chased down from the right side.
2. Rush Linebacker: Another position that Indy foolishly probably thinks has been addressed. Walden was signed away from Packers, whose defense got noticeably worse every time he was on the field. If he can hurt a talented defense as a backup, why would you make him a starter on a mediocre defense? I really hope they don't think he is the solution to replace Freeny, they should take a rush linebacker with one of their earlier picks.
3. Cornerback: The Colts made a decent move in bringing in Toler, but he should probably be more of a nickel corner. If Indy feels the same way, they will probably be looking for someone to start across from Davis. They could take a corner as early as round one.
4. Defensive Lineman: The Colts have a decent trio of players to play on the ground of their 3-4, but lack any impact players. If Indy just wants to take the best player available, they could easily take a DE/NT with their first round selection. If not, they will probably use a mid to late round pick on some depth.
5. Offensive Guard: Bringing in Donald Thomas was the best move the Colts made this off season. However, they don't have a stable guard accross from him. I think they will give Linkenbach another shot, but they should bring someone in with a later pick to provide some competition. The rookie might even have a shot at getting the starting nod.
6. Running Back: Vick Ballard was a pleasent surprise, and will go into the season as the starter. However, he's not a game changer and doesn't have much behind him. They should probably pick up a running back with one of their last picks and hope he become this years' Alfred Morris.