you'd be dumber then a door knob not to draft him and see what he has to offer after sitting behind peyton for a few years.
Or, we could trade down in the first round, acquire additional draft picks that would allow us to select multiple upgrades for our defense, OL and WR positions out of the very talented overall draft class for next year. We could either draft Luck #1 and see what he can do 3-4 years down the line after Manning retires, or we could acquire even one additional draft pick in this years first round (not at all impossible with cleveland having 2 first rounders) and get the NT we need in Alameda Ta'mu, the elite CB we need in either Dre Kirkpatrick or Morris Claiborne (the Polians do love their LSU Players lol) and immediately upgrade arguably our 2 weakest positions. Then select another UT in a later round so we can move Eric Foster to DE where he belongs and use the rest on any combination of WR, LB, OL. Now we're back to having more than a legitimate shot at winning now instead of in a few years.

I'm also a regular poster on the colts.com forum and here is just part of my reasoning for not drafting Luck at #1:
I would personally without a doubt trade down and acquire extra picks.
1-Atlanta gave up an arm and a leg to draft up and get Julio Jones. Cleveland (who has 2 first rd picks this year) has shown they have no problem packaging picks and trading up ala Brady Quinn. With all of the hype Luck is getting, I think there's no question that a bigger deal could easily be made for him than the Atlanta deal last year. Acquiring extra draft picks would go a long way towards helping us shore up some areas of weakness in what is going to be a very strong draft class.
2-There are so many people posting on the forum about how much more success Manning could have had with a better defense and running game and I agree. I'm not saying we haven't been successful, that's absurd. However I do think if we had continued to maintain a running game like we had when Edge was here then our offense would have, imo, maintained a higher degree of explosiveness than what we've seen the past few years. Same can be said of our defense...how many more championships could we have won if we had a stronger defense? I do think our D is improving and we'll see even more improvement if they learn the right and wrong times to use the tampa 2. However, we still have strong needs at CB and DT and other less-critical areas where at the very least we need better depth. Also we don't need just any DT but rather a NT. Of all DT's that come out in the draft only a portion of them are capable of playing a true NT position so the ones who can play NT and at an elite level are generally off the board relatively quickly. Same can be said of CB. There is going to be a lot of talent at CB in the draft but we have to ask ourselves if we really want to keep taking chances with lower round guys to step into the starting lineup instead of pulling the trigger on a high-level prospect where the risk is much less. So yeah, by trading down and acquiring additional picks we can shore up these holes as well as bring in some additional depth at several other positions.
3-Some QB's you bring in to groom for a few years and some you bring in and put them right in the starting lineup. Luck appears to be one of those that you bring in and start right away ala Manning, Manning (eli), Bradford, Stafford, Flacco, Ryan etc. I recall reading somewhere (unfortunately don't have the link so believe me or don't) that Manning said he felt one of the things that helped him the most was starting right away. If he's as polished and NFL ready as people claim him to be then it would almost be a disservice to him to have him ride the bench for the next 3-4 years while Manning is still here. The QB's that you bring in to groom for the future are guys who there are question marks around. Whether it be with their leadership ability, throwing mechanics, them coming from a spread-type offense or any number of other potential question marks. You ride these guys on the bench behind a veteran so they can learn how to play the position better. From all that is said about Luck I don't get the impression he's one of those types of QB's. I have no problem with looking to bring someone in to compete with Painter in attempt to upgrade the backup spot but if that's what we're looking for then wait until the 3rd or 4th round.
4-So based on #3, the only real reason that would make sense to have Luck be "groomed" by Peyton is to give Luck opportunity to learn our offense and scheme. This makes little sense to me. Anyone who thinks there is another QB who will come in and be able to do the things Manning does is expecting way too much. I'm not going to say for certain that Luck or another QB could definitely not do it, but the fact that there's not another QB in the league today who has as much control of the offense as Manning does and that to go back through history, the closest and most recent example would be Jim Kelly of Buffalo..and that was late 80's/early 90's. When Manning goes...so does the amount of control the QB position has goes as well. When Manning goes we are going to have to make adjustments, make things less complicated from the QB perspective and the offensive coaches are going to have to be more involved in play calling and game planning etc. Not saying that they're not involved now, but with Manning they don't have to be as involved as they are going to have to be with any other QB. So why bring Luck in to learn a system he likely won't be running anyway?
5-Based on #4, we should spend every resource available to us to build a better team around Manning while he's still here. Not only does this seem to be the right thing to do for Peyton and to give him a chance to retire with more than one ring, but in waiting to address the QB situation we are building a much better team so that when the time does come and we have to find our next franchise QB, we have a much, MUCH better team built around him and that will make things a lot easier for him and should mean success much earlier.
6-Everyone compares the situation of Manning grooming Luck to Montana/Young and Favre/Rodgers. This goes back to my 3rd point...Young wasn't even drafted by San Fran, they acquired him from Tampa Bay where he was riding the bench. Rodgers was a late first round pick, not a top 5 pick. Neither of these teams went out and spent the #1 pick on the top QB prospect of the draft and then spent the next few years developing them. These were both guys that had areas of concern and aspects of their game that needed to be polished before they would be considered ready to be a full time starter in the NFL.
7-We can continue being a team that's built entirely around a GOAT caliber QB and base all of our success on him, meaning any time he has a subpar game...we lose. Or we can build a much better team first, one that can stand on its own 2 feet regardless of how the QB plays and then we go out and find our next franchise QB.