Mine are long and skinny, but I still ran into that same leverage issue by about by 6 months of age. After that, they generally carried better on the back due to weight unless I loaded up a backpack to counterbalance them. Shedding heat also became an issue with a baby on my stomach and a daypack on my back.

The Ergo carrier is a COOL carrier, by the way - my wife likes it way better than the massive Kelty backpack I use when I'm hiking, and I'm coming around to her way of thinking.