Since hiring Jeff Luhnow back in 2011 to be their general manager, the Houston Astros have undergone a massive rebuilding project.

In the midst of averaging a whopping 104 losses from 2011-2014, however, they were able to stockpile some serious talent.

And finally, after a ton of losses, three consecutive first overall draft picks and three successful draft hauls, things are looking up in H-Town.

In the 2015 season, the Astros were arguably the most surprising team in the league. They won 86 regular season games - their highest total since 2008 - defeated the New York Yankees in the American League Wild Card game and then came within a few outs of beating the eventual World Champs in the ALDS, when a chaotic eighth inning in Game 4 forced a decisive Game 5, which the Astros could not win.

Despite the disappointing ending, the season was still wildly successful. 21-year-old phenom Carlos Correa showed tantalizing potential in his rookie campaign, Dallas Keuchel established himself as one of baseball's elite starting pitchers, and A.J. Hinch showed that he is one of the best managers in Major League Baseball.

All three of them were named as one of three finalists for the American League Rookie of the Year, Cy Young and Manager of the Year awards, respectively. The winners will be announced next week, November 16-19.

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However, as much success as the Astros enjoyed in 2015, that is now in the past and it's on to the next item on the agenda: do whatever they can to improve the team over the offseason, and put a team on the field to commence Spring Training that is even better than the team that had the third-best run differential in all of baseball.

The tricky part of that: there aren't really many aspects of the team that stick out as major weaknesses.

Last year, it was the bullpen. But with the additions of Luke Gregerson and Pat Neshek as well as the emergence of Will Harris, the Astros possessed a stout core of relievers that was one of the best in the league.

Before talking about what this team needs, let's talk about how much talent this teams has and why there is certainly something special brewing in H-Town.

Correa might be the cornerstone of the franchise - after all, he possesses game-changing power that is rarely, if ever, seen at the shortstop position these days- but he's far from the only weapon that the Astros have.

Second baseman Jose Altuve has established himself as one of the best hitters in the game, due in large part to his uncanny ability to put the ball in play, no matter where the pitch is thrown. He won the AL batting title in 2014 after he hit .341, and he followed that up by once again leading the league in hits with an even 200. Add in the fact that he has led the AL in stolen bases the past two years, and he has as good of a case as any as the best second baseman in all of baseball.

The outfield is loaded with talent as well. With George Springer in right and Carlos Gomez in center, the Astros have two dynamic athletes that can hit for power, run down balls in the outfield and create runs on the basepaths.

Add in playoff star Colby Rasmus - who on Thursday became the first player in MLB history to accept the one-year, $15 million qualifying offer - and speedy Jake Marisnick to the mix, and the 'Stros have one of the best outfields in MLB.

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Designated hitter Evan Gattis didn't fulfill the lofty expectations that were bestowed upon him when he came over to Houston from the Atlanta Braves, but he did knock in a team-leading 88 RBI and was a solid middle-of-the-order hitter. He should be able to improve on his .246/.285/.463 slash line in 2016.

Jason Castro left much to be desired at the plate last year, but what the Stanford alum did behind the dish is what makes him so valuable. He was one of the best catchers in the league at blocking and framing pitches, according to Stat Corner, and with him hitting in the bottom part of the order, any runs that he produces with his bat can be considered simply a bonus.

Keuchel has a good chance to win the Cy Young award when it is announced next week. (Al Bello/Getty Images)

The starting rotation projects to be a major strength for the Astros as well, not only in 2016 but for years down the road. Keuchel got most of the credit - and deservedly so - but the breakout rookie season of Lance McCullers was critical down the stretch last year.

Veteran Collin McHugh earned 19 wins on the bump last year, and he proved to be a durable middle-of-the-rotation starter. Scott Kazmir, whom the Astros acquired from the Oakland A's last July, pitched superbly until his last handful of starts. He is now a free agent, and while the front office is certainly interested in re-signing the 31-year-old lefty, it won't be just to make last season's trade look better.

“We traded for Kazmir because we wanted Kazmir for the balance of 2015 and for the playoffs,” Luhnow said, via Evan Drellich of the Houston Chronicle. “That’s independent of who we see Kazmir as as a free agent candidate for us going forward. The two aren’t linked. I think it would be irresponsible of me to want to sign him moreso just to justify a trade that is already over. I mean, that trade is over.

“Now, we got to know Kazmir. He’s comfortable in Houston. There’s things that we really liked about him, so that would lead us to want to be interested, but … nothing about our desire to sign a free agent relates to how he came to the organization.”

So the Astros have an offense full of talented, athletic game-changers and a starting rotation that brings to the table a nice mix of youngsters and veterans.

What do they need to do in the offseason to bolster the team and maximize their chances of returning to the playoffs again in 2016?

Well, the biggest need is at first base. Chris Carter had an outstanding year two seasons ago when he walloped 37 home runs and drove in 88 runs, but his putrid showing in 2015 suggests that his second half explosion two years ago might have been more of a fluke than the makings of a good hitter. He regressed in every meaningful category - he posted an OPS+ of 77, which means he is more than 20 percent worse than the average MLB hitter - which is why the Astros must scour the market for a new first baseman.

Actually, they don't have to look very far. Chris Davis is the best position player on the market and is someone whom the Astros should pursue. He is a Scott Boras client - so he will not come cheaply - but his powerful left-handed swing would exponentially increase the productivity of the offense and make it one of the most feared in all of baseball.

Adding an elite power hitter like Chris Davis would immediately put the Astros in the conversation as the best offensive in baseball. (Otto Greule Jr/Getty Images)

Third base is also a bit of a concern, but it could be worse than having two veterans like Jed Lowrie and Luis Valbuena manning the position. At least the 'Stros know what they are going to get out of those two players, and since Lowrie is a switch hitter and Valbuena is a lefty, Hinch could elect to platoon them.

And then there's the bullpen. In today's version of baseball - where starters are throwing harder and pitching fewer innings than ever before - having a deep, effective bullpen is integral to regular season and especially postseason success.

While Houston's bullpen performed excellently last season, the old adage is that you can never have too much pitching.

It is no secret that several elite closers are being shopped on the trade market, and the Astros' front office should certainly keep their minds open. The popular belief - especially in an analytics-driven franchise like Houston - is that paying top dollar for top-of-the-line closers is a losing investment. Even if that is the case, if they can get a bargain for a bullpen ace like Craig Kimbrel or Aroldis Chapman, adding an arm of that caliber would work wonders for the Astros' postseason chances.

The Reds have not been bashful about trying to trade their flamethrowing closer. (Joe Robbins/Getty Images)

Houston's general manager admitted that they are pursuing that avenue, but also made it clear that they are not going to overpay.

“Those conversations are happening and it really comes down to what our options are, either through trade or trying to improve the bullpen through free agency and how much it’s going to cost in terms of prospects or money to put something together,” Luhnow said, per Drellich. “You know, nothing’s cheap.”

Whatever the front office decides to do this offseason - even if it is nothing - the future in Houston is incredibly bright.

Each member of the Astros core - Correa, Altuve, Springer, Gomez and Keuchel - is younger than 30 years old, and Houston's farm system was recently named the best in all of baseball by MiLB.com.

The Astros made tremendous progress between 2014 and 2015, but that was just the first step. Expect them to improve again in 2016, and continue to get better after that.