I personally believe that happiness is more important than intelligence. For example, you could be extremely smart, but could also can not happy at the same time, it doesn't make life any fun. Just because you are smart doesnt mean that you automatically have a happy life. Sure, intelligence may get you a good career, but to me its not as important as being actually happy in your life. You only live once and you should enjoy your life rather than making sure you're the smartest; if you're not actually happy with the life changing choices you made.
(This is how I would word this)