To them, being balanced means putting in the most appropriate amount of going to boasting sessions, door to door, street work, "informal" witlessing, calls, studies, hounding calls, running the boasting sessions, preparing for boasting sessions, studying the puketower litter-ature, and helping others to do the same. Each of those activities had to balance the others so your time could be exploited to the maximum advantage of the cult.
Notably, other activities are weeded out. They call it unbalanced if they can take any segment of your life out of context, and you are doing something playful (listening to music that doesn't have a number between 1 and 225, sports, picnics, and the like), you are not sacrificing enough. They also want to reduce sleep time to the core minimum to allow more time for those letter writing sprees and for getting up at 5:30 in the morning for street work. Eating has to be done on the fly, leading to the infamous Pioneer Diet. All activities that are normal human activities are in the way of getting the message out.
And yet they refuse to construct robots to get the message out. As I see it, one spambot can get the message to everyone with Internet access in about 5 minutes (and if you don't believe me, just ask Wal-Mart. They can get their flyers onto everyone's e-mail inbox in minutes.) Instead, they need people to give up their lives and do it the slow way, wasting gas and car wear and tear in the process.
Balance should mean putting ALL human activities in proper places. We all need to work, but I wouldn't want to work 24 hours a day, 7 days a week without any time off. We all need sleep, but again we don't need to always be sleeping (otherwise we would be dead). That also goes for play. We also need plenty of time to eat (and I definitely do not recommend eating Big Macs or Whoppers for lunch every single day). Cleaning the house is another thing that needs to be done. Maintaining and repairing (or replacing) things is also necessary. Then there is need for entertainment. Granted, if one had the perfect job, they would feel like they are playing while working. This, however, is extremely rare. And, going out in field circus definitely does NOT qualify as satisfying work.