TL;DR: The Colts can't just draft "BPA"
When taking draft strategy, the common suggestion is "best player available at a position of need". I'm writing this FanPost to make a simple argument: that's a bad strategy. I prefer what I've called the "value-over-alternative" approach.
It is important to remember that players are not selected in a vacuum, they are selected both at the expense of selecting another player at a different position, but also at the expense of selecting a player at the same position in a later round. Rather than simply draft "BPA", the team should draft players who have the highest "value over alternative"--meaning the difference between the talent level of the target and other players at the same position available later in the draft. For example: let's say you are the GM, and you need to draft a guard and a corner. In round 2, you have two prospects available: a guard who projects as a Pro-Bowler, and a corner who projects as a near Pro-Bowler. However, you know in round 6, you will have two more prospects available: a guard who projects as a solid starter, and a corner who projects as a border-line CB4. In this case, even though the guard in round 2 is the BPA, the corner in round 2 provides more value over alternative.
Think about it this way: you are given the chance to pick between two envelopes of money, each containing two stacks of cash. The first envelope has contains a stack of $50 and a stack of $5. The second envelope contains a stack of $40 and a stack of $10. You wouldn't pick the first envelope just because $50 > $40; you would take the second envelope because the total value is greater. We need to apply that same theory to the draft. Let's take a look at some common potential scenarios in the upcoming draft.
As I see it, here are the Colts' biggest needs, in order:
1) Guard: Right guard is currently the weakest position on the team. I hope as much as the next guy thatHugh Thornton will go from being one of the worst guards in the NFL to a capable starter, but as a general matter that rarely happens. I'm not saying it can't or won't, just that it isn't likely to. We are in even deeper trouble if Donald Thomas can't regrow his muscles (if I recall correctly, he tore roughly all of them).
2) Free safety: Like many people, I believe safety is a huge area of weakness for the Colts. Right now, the pairing of Delano Howell and the Glass Bicep is certainly serviceable, and would do an adequate job. However, one of them is going to miss significant time. It isn't a question of if, it's a question of when. For that reason, obtaining another safety is not a matter of adding depth (even though the team already has two starters), it's essentially a matter of adding another starter.
3) Center: I hope Khaled Holmes can play. I just don't have faith in a guy with so many question marks. There have been tons of reasons tossed out about why Holmes never saw the field last year. I don't buy the argument that he was not strong enough--he was a multi-year starter at USC--but I do buy that perhaps he was essentially red-shirted to give him time to get completely healthy. Hopefully that's it. However, it could just be that Holmes is not that good a player. For that reason, it's going to be important to have a back up plan (and for anyone saying Phil Costa can turn it around...well, I just feel bad for you).
4) Nose tackle: Josh Chapman is not the difference maker we hoped he would be. Either a) he was not better than Franklin last season or, just as likely, b) he was better but the coaching staff refused to start him because they refuse to bench anyone (see: Angerer, Pat). When he was in, he was okay, but if this defense is going to succeed, it needs as many true difference makers as it can get. In this case, a better nose tackle will free up Redding and Jones to terrorize the inevitable single team one will get, and it will let Robert Mathis do what Robert Mathis does. In so doing, it will take pressure off the secondary. In short, upgrading the nose tackle position is the single most impactful change the team can make to its defense (short of finding a new, actually-competent defensive coordinator).
5) Corner: Toler will miss time, and when he isn't missing time he won't play that well anyway. Josh Gordy is a great back up, but he isn't a starter. The Colts could use an upgrade.
6) Strong safety: Laron Landry sucks. Like....really bad. He was great before he got injured, but ever since then he was a huge liability in every aspect of the game. His calling card is his monstrous hits, but he seemed to miss a majority of his tackles because he simply refused to just wrap up the ball carrier.
7) Inside linebacker: Jackson was a decent signing, but the Colts still need someone else in the rotation.
8) Outside linebacker: Erik Walden played decently in setting the edge, but he couldn't cover very well (not that he should be asked to do that--but Greg Manuksy is basically illiterate so I'm not surprised he was). It might be nice for the Colts to look for an upgrade or a future replacement. Josh McNary might be the answer, but, again, that's a risky proposition. We also need an OLB to take over the pass rush, but I'm less concerned about that for several reasons. First, an improved d-line will help the pass rush far more than a second pass rusher will. Second, Bjoern Werner showed the most potential of any Colts rookie or FA signing last year; he should be come at least an average starter. That certainly isn't enough, but the Colts can worry about adding another pass rusher in the next draft--there simply are not many blue-chip pass rushers in this one, so there is little chance one will fall.
With needs established, lets move on to examining some potential scenarios that could arise during the draft. I've watched oodles of tape on players at these positions, ranging from high-end prospects down to UDFA candidates. I rarely watch highlight tapes, and I don't consider scouting reports as much as I consider my own eye test. Stats are suggestive of a player's ability, but in no way are they conclusive of it. College awards (being named to all-conference, position awards, etc.) are meaningless.
Here are some players I've watched that could fill needs, organized by position (round--potential)(NOTE: an "average starter" is a player who isn't great at anything, but isn't a liability in most things, either):
Guard: Gabe Jackson (2--perennial potential Pro-Bowler), Cyril Richardson (2-3--good starter), Brandon Linder (5-6--average starter), Zach Fulton (7-UDFA--average starter), Spencer Long (UDFA--average starter)
Center: Travis Swanson (2--good starter), Bryan Stork (3-4--good starter), James Stone (6-UDFA--average starter)
Free Safety: Jimmie Ward (1-2--good starter), Terrence Brooks (2--above average starter), Kenny Ladler (5--above average starter), Ricardo Allen (6-7--great starter), Nickoe Whitley (7-UDFA--average starter), Brock Vereen (7-UDFA--average starter)
Nose Tackle: DaQuan Jones (2-3--near Pro Bowler), Will Sutton (2-3--great starter), DeAndre Coleman (5-6--average back up)
Corner: Stanley Jean-Baptiste (2--great starter), Jaylen Watkins (3--average starter), Walt Aikens (5--good starter), Aaron Colvin (5-6--above average starter)
Strong Safety: Terrence Brooks (2--good starter), Dion Bailey (3-4--above average starter), Vinnie Sunseri (5-6--average starter), Brock Vereen (7-UDFA--average starter)
Inside Linebacker: Christian Jones (2--great starter), Adrian Hubbard (4-5--great back up/average starter at 3 positions--ILB/OLB/3-4DE), Greg Blair (7-UDFA--average starter)
Outside Linebacker: Christian Jones (2--good starter), Carl Bradford (2--good starter), Adrian Hubbard (4-5--great back up/average starter-see above), Ron Powell (5-6--average starter), Devon Kennard (6-7--average starter), Boseko Lokombo (7-UDFA--good back up)
So, given roster needs and the above information, it seems clear that BPA at a relative position of need is Gabe Jackson. He has the potential to be on the cusp of a Pro Bowl nod perennially. It also just so happens that in this case, he also provides the best value-over-alternative. If Cyril Richardson were guaranteed to be around in the third, Gabe Jackson might become less valuable, but it is more likely than not that Richardson will be gone by pick #90.
Even if Richardson were there, however, it is much more important to draft an NT in the 3rd round, as both of their values-over-alternative are off the charts: if the Colts do not get either DaQuan Jones or Will Sutton, there is no one left in the draft who could be even a below-average starter at the position. DeAndre Coleman would be a huge liability on passing downs, and everyone else is just..well..better suited elsewhere. This is true even if the Colts fail to land Jackson in the 2nd and Richardson falls to the 3rd; there are average starters available at guard later on.
Another great example is free safety. A number of posters here believe that the Colts should address free safety with their first pick. By my estimation, the best two safeties the Colts have a shot at landing are Jimmie Ward and Terrence Brooks. Both of those guys are quality prospects who have similar ceilings. However, if the Colts draft one of them in the 2nd round, that means they will have to pass on a Guard in the second round. Because the Colts will have to take an NT in the third round or fail to draft one entirely (which would be a mistake), the next shot the Colts would have at a guard is in the fifth round with Brandon Linder. The result is that the Colts would have an above average starter (safety) and an average starter (guard). If the Colts pass on a safety in the second and instead draft Gabe Jackson, the Colts could grab a safety in the fifth, sixth, or seventh round. At worst, the Colts would wind up with a potential Pro-Bowler (guard) and an average starter (safety). Pro-bowler + average starter certainly beats above average starter + average starter.
Again, the goal should be to maximize value over alternative, defined by the difference between the prospect and an alternative available later on. In other words, if we think of value over alternative as a number (e.g. Gabe Jackson is worth a 10, where Zach Fulton is worth a 4, which provides a value over alternative equal to 6), the goal should be for the Colts to have the highest number possible if all their picks' values over alternative were added together.
I know this has been long and kind of poorly written--I've had a rough few days and this is what I do to relieve stress, often at the sake of good writing.
Let me know what you guys think.