I understand "most people" locally -- that's most of those people who form your society and who influence your culture and political decisions. Were you thinking of some sort of global referendums and, by implication, a global government?

No, I was thinking of ideas that are so universal that they're not even culture-dependent or politics-dependent to any significant degree. Pretty much every sighted person thinks blindness is bad.

If you don't trust the "past" people to change your gene pool, what makes you think "future" people will trust you to change their gene pool?

Even though present-day people aren't perfect and can make mistakes, the overall trend is asymptotically towards making fewer mistakes and the difference between past and present should not be the same as the difference between present and future. Furthermore, I don't claim that what everyone agrees on would be exactly correct, only that the risk of being over-inclusive is not significant.