Just use Luck as a platform because QB is the easiest platform to build good offense off of. That’s why they are highly sought after.
So, the core of making a good Colts team is this: simply make Luck into a better QB by making his position as a QB easy.
1) Give him good protection, so he can throw more accurately.
2) Give him better receivers so they can catch his passes.
3) Give him a good RB with some HBs to make Luck’s job easier.
4) Give Luck a good defense so he doesn’t have to march all the way across the field and to score as much points.
5) Give Luck a good special teams unit so by having a good field position, so he wouldn't have to throw as much to produce yards, thus making Luck's job easier.
6) Give Luck a good crew of coaches and management to put it all together.
Guys like Manning, Rodgers, Elway and the rest seem amazing because they excelled regardless whether or not if their jobs as a QB was challenging since they’ve lacked the tools (good defense, good offensive line, lack of running game, etc) needed to make their jobs easier, right? And then we got guys like Alex Smith, Trent Dilfer, Matt Schaub whose jobs are easy, so they are better QBs as result.
So, just by making Luck’s job easier as a QB, you make him into a better QB. And when you make Luck into a better QB, you have a good team as result. When you have a good team as a result, you make Luck's job as a QB easy.
In a single off-season of 2013, start with an offensive line during free agency and then draft the best available defense. Or start with a defensive line during free agency and then draft best available offense. Either way, the team won't be complete within a single off-season.
(Speaking of such, it's fun to consider that the Jags could be a good team in 2-3 years. Guaranteed. How? Make Maurice-Jones Drew's job easier as a RB. Use him as the team's platform in winning. Give him a good #2 RB for rotation, several HBs, good offensive line, good defense and special teams. Despite Gabbert being your #1 QB, the Jags can still challenge for the AFC South crown.)