Astros at the halfway point: What have we learned?

With June swooning into the past and July sparkling on the horizon, the Astros have officially played half their schedule. At 36-47, the Astros are also six games above their 30-52 pace from 2013.

What's more, the Astros have chopped their run differential in half from where they were a year ago. In 2013, opponents outscored Houston by 112 runs through the end of June. In 2014? They've only been outscored by 52 runs and have actually outscored opponents by two runs since the beginning of May.

That has the Astros on pace to finish with 71 victories, which would be the most they've won in a season since 2010. And, what's even more amazing, the Astros are only the fifth-worst team in the league (by winning percentage).

All in all, the Astros can say they improved in the first half of 2014. Let's look at the team and see what we've learned through 83 games.

Jose Altuve is back.

Houston's second baseman has put up the 21st-best season in the major leagues, according to FanGraph's WAR. He leads the American League in steals, leads the majors in hits, has the second-fewest strikeouts in the majors among qualified hitters and trails only Troy Tulowitzki in batting average.

No Astros has ever won a batting title, in either league. Since June 12, Altuve is hitting .509 with 12 steals in 14 games. He's not likely to continue that hot streak, but he could be the first Astro since Berkman to challenge for that AL batting title.

What a change from the end of last season, when many were writing Altuve off and penciling Delino DeShields or Nolan Fontana in as the Astros 2B of the future.

Dexter Fowler wasn't a Coors Field mirage.

When Houston sent Jordan Lyles and Brandon Barnes to Colorado for Dexter Fowler, one of the most common refrains was that Fowler wouldn't hit nearly as well away from Coors Field. His road splits were horrendous and that's likely to be his new baseline, the storyline went.

Flash forward to the halfway point. Fowler is hitting .270/.377/.396 and has been even better after a slow April. Since May 1, Fowler has a .408 on-base percentage and an .820 OPS, giving him a wRC+ 37 percent better than the league.

Overall, Fowler has the ninth-highest on-base percentage among major league outfielders and the 20th-best wRC+ this season. His power is down from the career-highs of 2012, but it's only slightly lower than his career .420 slugging percentage. Oh, and Fowler's also on pace for 610 plate appearances, which is easily a career-high for him.

George Springer was ready for the majors.

Mike Cameron 2.0 has fit his billing nearly perfectly. After a very slow start, Springer heated up in May and has been Houston's most powerful hitter. He's got the most home runs on the team, the highest isolated power average, the highest slugging percentage and the second-highest wRC+.

His defense is shaky at times. At others, he dons his cape and makes a "super" play.

He's gone through another slump since his early-season one, but continues to be Houston's biggest threat in the lineup. How else can you explain the Tigers walking a .240 hitter twice in Sunday's game?

Yes, George Springer has made the transition to the majors nicely.

The rest of the lineup is shaky at best.

Outside of those top three, only one other Astros batter has a wRC+ of 100 or better and that's backup catcher Carlos Corporan. The other six regulars in the lineup all are at 88 or below, meaning the best of the rest is still 12 percent worse offensively than the rest of the league.

Despite finally calling up Jon Singleton, Houston has gotten zero production out of first base, as Gator transitions to the big leagues. Left field has been a black hole of offensive production, with a revolving door of guys like Robbie Grossman, L.J. Hoes, Alex Presley and Jesus Guzman all seeing time out there.

Jonathan Villar opened the season on a hot streak, but has quickly fallen back both offensively and defensively. Matt Dominguez has slumped badly, too. Chris Carter is doing Chris Carter things.

But, the one guy that's hurt Houston the most is Jason Castro. While his defense has improved, he's been below-average offensively this year. Even if he were at 80 percent of his 2013 performance, Houston's lineup would be much more balanced. As it is, the Astros struggle to hit consistently after their top three guys.

This is a problem that won't just be fixed by calling up another inexperienced rookie. It's also one of the biggest storylines heading into the second half.

Collin McHugh surprised.

It's all about pitch tunnelling. Scrapping the two-seam fastball in favor of four-seamers up in the zone has made that pitch and his curve more effective, turning a journeyman 26-year-old on his third team into a legitimate No. 2 starter for the Astros.

His strikeout rate has risen 10 percent from a brief 2012 stint with the Mets and up nearly 20 percent

McHugh will not post a sub-3.00 ERA for the rest of the season. But, he has been a major find for Houston's scouting department. He's also young enough to stick around for the next few years, making him an even better find.

Dallas Keuchel may be making The Leap.

Raise your hand if you had Dallas Keuchel as Houston's best pitcher heading into the 2014 season. Okay, Chris and Tim, put your hands down. Everyone else? No, I didn't think so.

Keuchel has just been outstanding through the first half of 2014. He's lowered his walk rate once again while raising his ground ball rate by eight percent. He's also the only starter in the majors with a ground ball rate over 60 percent right now.

How good has Keuchel been? Multiple national writers have floated the possibility of Keuchel joining Altuve on the American League All-Star team. If two Astros in the Midsummer Classic isn't a sign of progress, I don't know what is.

Regression didn't bite Cosart.

My biggest surprise this season is how good Jarred Cosart has been. Though his stuff is electric, he's never been a big strikeout guy. That cut fastball he throws, though, has helped him get plenty of weak contact. Combine that with a mechanical adjustment made by Brent Strom to make his delivery more repeatable and Cosart's walk numbers also dropped.

Right now, he's comfortably one of Houston's three best starters. In the past four starts, he may have been Houston's best pitcher, period. He's still got the best chance of any Astros starter to throw a no-hitter and gives the Astros plenty of upside in the middle of that rotation.

Given how bad Houston's pitching was last year, having three pleasant surprises all in the rotation has got to be a victory for fans.