The reason they want people with leadership qualities to progress is because Chuunin become squad leaders. The ability to think through things rationally and not endanger your team are the qualities that truly stand out among Chuunin. It's not the level of Jutsu you know, and it's not how strong you are.

"If you're a ninja, act like a first-rate one." Morino Ibiki

This quote sums up the true meaning of the Chuunin exam. Resourcefulness and cunning.