I think the problem is that intelligence is not enough. I think even Solomon observed that the wisest amongst us can be socially ostrasized to die poor and ignored. Heaven knows our world leaders desperately need intelligent people supporting them. But it is not necessarily the wisest who rise to the top, but the most politically astute.
Maybe because so many in my family are mentally ill. Or my interest in learning disabilities. But I have seen up-close-and-personal what happens when a key component to intelligence is missing. I have some genius-level relatives whose imbalanced magnificent minds have incapacitated them. No balance. Plus they are rude. No time for ordinary folks.
A mind is part hard-wired, part made. If a young child is not exposed to a fully-functioning language before they are four, they are handicapped for life. So I think the ability to manipulate language is essential to intelligence. Language gives us self-talk, allows us to rearrange events before they happen, and consider the outcomes.
I know that my mind is highly indexed. If the information is easily accessible elsewhere, I don't bother retaining that information. Call it a "lazy mind". My hubby, on the other hand, has no internal map. He relies entirely on his prodigious memory to function. He has to work hard to get information to work for him.
Yes, we have a few empirical measures of intelligence, but just because we can't measure some of the things the mind does, does not mean that they are not essential, such as social intelligence. The ability to read people's behavior and deduce what motivates them.
So, we are in a pickle. Yes, flexibility is important, but so is balance. We are necessarily forced in to an artificial structure (language) that forever limits our perceptions. I know that my ability to map concepts in to a cohesive matrix is very useful for managing complex problems, but without some sense of social awareness, my discoveries die with me.
To build the perfect mind, I think, is not an either-or, black and white, right or left brain decision. We are a complex mix, and any overbalance of any single component can render the intelligence useless.