I agree that the word intelligence is too vague, but I'm specifically not including a mathematical genius (who would have an exceptional talent in the area of mathematics).

I strongly disagree that average people can't or don't have utilitarian inclinations. I think utilitarianism is one of the easiest philosophies to grasp, and I know a lot of average-IQ people who express the desire to "do as much good as possible" or "help as many people as possible." Even the advertisements for charities that you mention tend to stress how much good can be achieved with how little money.

It's certainly good to customize advice, but I think there is a class of advice I would offer to smart, skeptical people that I would hesitate to give to others. For example, I would tell my brightest students to question expert advice, because then they can more deeply understand why experts think what they do, or potentially uncover a true fault in expert reasoning. With my less-bright pupils, I find that this pushes towards conspiracy theories and pseudoscience, and thus more frequently advise them to trust experts and distrust people on the fringe. When smart people question mainstream scientific thinking, they may go astray. In my experience, when average-or-below intelligence people question mainstream scientific thinking, they almost always go astray, and when they don't it's usually coincidence.

I'm trying to figure out how to help them understand things more deeply and question things in a more productive manner, and definitely borrowing lots of ideas from LW, but I still think there is a lot more room for improvement.