When I was in college, I worked in retail, and the staff issues there were pretty simple. If there was extra work, more staff was hired.
That was my take when the SuperLiga was first announced. I was surprised that the league hadn't expanded the rosters. It just made sense - if teams were going to do more work, to have more players on hand to bear the load.
Depth is probably the biggest issue for most MLS teams today. The Galaxy are a prime example of that, but so is Toronto, for instance.