It isn't a matter of balancing the runs with the passes...it's a matter of making them compliment each other, and using the best available plays against what a defense can/can't do. In the playoffs, the QB usually has to be able to make big plays because you tend to go up against better defenses. The "balance" will be that the Packers ability to run this year will not only draw the safeties up, as mentioned, but will prevent teams from being able to sell out with personnel packages for the pass rush and coverage, because they'll get it rammed down their throats.
The other thing it allows is the ability to grind out clock late in the game when protecting a lead. Sometimes the best defense is to keep the ball out f the hands of someone who can make big plays and win games...like Kaepernik, Manning, RGIII, Stafford to Johnson, Cutler to Marshall, Flacco, Roethlesberger, Dalton to Green and Ryan. ALL of whom are on the schedule this year.
In addition, a 3rd and 1 or two when you can run more reliably means Lacy or Franklin are a better option than throwing or trying to sneak with A-Rod every time...and if they stack the line to stop it, play action passes will eat them up.
It might mean calling only 20 eushes per game, but if those are used more effectively, the 40 passes will bring that yards per pass number back up and ultimately more points on the scoreboard.
"The difference between genius and stupidity is that genius has its limits" --Albert Einstein