As I view the matter, IQ measures processing capacity, your ability to manipulate spatial, numerical or verbal data accurately and quickly. The person with the high IQ finishes the math test first. They are the first to assemble the something that needed assembling. They know facts and figures about the world, and they tend to use grammar correctly.
All of these things are important. In general, given equal characters, the smarter person will always accomplish more than a dumber person.
At the same time, IQ does not imply a capacity for imagination. Einstein himself said that imagination is more important than intelligence, and the reason he said this, in my view, is that the most useful thinking operates not on existing information, but potential information, paradigmatic information.
IQ enables you to easily navigate existing trails. You can go farther, faster, with less trouble. But it does not necessarily allow you to go traipsing miles back into the bush, just to see what is there. That is a personality trait, one which implies courage, curiosity, and the capacity to imagine LACK, to realize that all the things we “know” may pale dramatically in comparison to the things we SHOULD know, and have been too arrogant, too paradigmatically fixated, to even pursue, much less find.
Let me put it this way: our Defense Dept. network was hacked some years back by a person in Russia using the most basic computer imaginable. It was not the processing speed which did it, but the creativity and persistence of the person operating it.
Tools matter, and intelligence is a tool, but the spirit operating that machine–and I do conceive of the brain as a machine, but one which I in a spiritual form operate–is what matters most.