How can I exploit him to my advantage
What would you consider an "outstanding achievement"?
He is a cousin of mine/my mother's*, I believe.
*[more related to grammar than to me being a legacy, but, in this context, would it be mother's, mothers, or mothers'?]
nor or little benefit
but submitting a positive and seemingly informed recommendation from a big donor can provide a huge boost.
Is this done in hopes of not alienating the donor?
Asians may face a road that is slightly more difficult than that for Whites (though I don't see significant evidence of this), but plenty still manage to get accepted (and in disproportionately high numbers). Consider these data. At Harvard, Asian applicants are over-represented by about 300%; White applicants have about 60% of what their proportional representation would be. At MIT, Asian applicants are over-represented by about 550%; White applicants have about 48% of what their proportional representation would be. Clearly, it is quite possible to get accepted, no matter your race.
Couldn't an asain applicant avoid this problem by simply choosing not to report their ethnicity?