There'll always be big countries, but that doesn't necessarily mean that it's staid and predictable.
You mention Ghana and the Ivory Coast as two of the big countries in Africa, for example. They qualified for the first time in 2006. Nigeria and Egypt are on the verge of missing out for the third and fifth successive time respectively. The countries who would qualify at their expense - Tunisia and Algeria - would in previous years have been in your list of the big five African countries, along with Morocco. That's just normal flux.
In asia, Japan's first World Cup was 2002, and 2006 was Australia's first since 1974. North Korea haven't been in since 1966. Honduras from Central America haven't been in since 1982. Chile in South America haven't been in since 1998.