There have obviously been a few concerns about a team leading a division for an entire season has only one All-Star. The Braves have had an NL Player of the Month and a rookie who won the NL Rookie of the Month for two consecutive seasons. The big issue the Braves individual players have had is that nobody has had three great months, whether that has to do with poor performance or injury leading to a lack of production over a given period of time.
If Justin Upton was just league average for the past 60 or so days he would have certainly gotten in and likely been a starter. If Freddie Freeman didn't hit the DL early in the year he probably would have enough home runs to justify being a first baseman on the roster. The same is probably true for Brian McCann, who is now sporting a .293/.378/.535 line and leads the team in FanGraphs WAR. One of his catching partners, Evan Gattis, would have had a great shot to make the team if he had not strained is oblique. If Mike Minor didn't struggle his past few starts he probably would have made it along side Kimbrel.
By now you get the point. To me, this is a good thing. The Braves are leading a division with nobody having necessarily an outstanding season. Their overall value has been hurt by either missed time or a stretch of poor play, yet the team continues to churn on and win games. Even Kimbrel is having a worse year than last year, which was probably to be expected (that was one of the best reliever seasons of all time).
The only player I would have put in, and the player I actually believe has been the most valuable member of the team this season, is Andrelton Simmons. Yes his hitting has been pretty bad and far below what was expected entering the year, but his defense has provided some incredible value this year.
The starting staff itself is not terribly impressive when you look at each individual starting pitcher. In terms of depth one through five they are definitely solid, but would you be surprised to know that the Braves have the second lowest team ERA in all of baseball? I was definitely surprised when I was doing a bit of research. Having the top defensive player at the most important defensive position is certainly a big reason for the team's ERA being as low as it is, especially when you consider how poor the defenders are to his right and left.
Even though I would put Andrelton in the All-Star game, I am not upset that he did not get in. It is doubtful that there will be a defense only type player put into an All-Star game, but if I had to pick a midseason MVP I think I would lean towards Simmons above all else.
To me, Kimbrel being the lone representative shows the quality of the 40 man roster that Frank Wren has put together. While the Braves have been relatively healthy compared to most of the league, they have battled bullpen problems and have had to move around their bench all year but still remain in first by a healthy margin. If some of their All-Star caliber players such as Jason Heyward, Justin Upton, B.J. Upton, and Dan Uggla put up All-Star caliber second halves, an even better half than the first should be expected.