This is a good point--I would phrase it as whatever over-arching organizing value set or decision-making framework you choose to use (whether it be "go with your gut", Rationality Uber Alles, WWJD?, "don't be a dick", or whatever) does not absolve you of responsibility for the actions you take according to that framework. Using rationality or moral values or whatever as a means to develop self-awareness and maturity is a valid and useful exercise IMO, but I know too many people who feel like "I'm just doing what XXXXX says I should do" excuses their actions even though it was still their choice in the first place to do what XXXXX says.

Also, Antonio Damasio's work is an interesting complement/counterpoint to the overemphasis of cognitive rational thinking, and I'd highly recommend it. Descarte's Error is a good place to start, and makes the strong case that rationality is part of an embodied (literally) process upon which it depends.

Why does one have to focus on being humane/considerate/farsighted instead of being rational, rather than focus on both? We don't have to pick one measuring stick.

I certainly hope you don't think that being irrational will help you to be more humane/considerate/farsighted, or that being humane/considerate/farsighted means that one can't be rational.