Thank you for writing this! You've made a lot of good points in here, some of which I've been thinking of myself.
A note on this point though:
Similarly, when considering whether to go vegetarian or take some other step to avoid participating in a major moral problem, consider how not doing so could validate and perpetuate the biases and selfishness that enable people commit that act normally, and how that act could help others feel licensed to do other selfish and harmful things that you disagree with, like lying to sexual partners about having an STI or being dishonest and uncharitable in representations of your organization or preferred cause area.
I generally agree with your position re: the potential harm of perpetuating harmful behaviors in the status quo by ignoring the moral issue of how diverse groups are treated. However, the vegetarian example used conflates declining to be vegetarian with "selfish and harmful" act of avoiding participating in a major moral problem. The problem is, there are a number of people in the world who have limited access to vegetarian substitutes and/or food in general, diverse cultural pressures, medical conditions, etc. which make changing their diet difficult or in some cases impossible. Therefore it may be more respectful and inclusive to caveat this statement by indicating that not all choices to abstain from vegetarianism are for simplistic or selfish reasons due to ignoring the moral problem.
Have you considered starting a research organization, or economic development think tank or consultancy in which your employees would do the day-to-day advising and 'politicking'. You could still be the entrepreneur who grows the organization and steers it forward.