Reading "The Message of John" (The Bible Speaks Today) by Bruce Milne (1993) as it is 'Holy Week' and hope to catch up with more Star Trek very soon. People can have clear ideas about right and wrong but still support a regime like that proposed by John Stuart Mill in "On Liberty" where very free speech and social experimentation are more than tolerated. IMHO (and I am not humble enough) the heteros in the books seem more libertine than the homosexuals. Perhaps only the requirements for some semblance of security could limit infinite diversity in sexual permutations.
I cannot well remember "Taking Wing" but each species shall come to understand, manage, and preserve (as well as conserve) the many variations of its genome and then perhaps experiment with increasing that diversity of which Spock was an all too logical example. Freedom from eugenics means monitoring and careful preservation and conservation of the genome and its variations.
Has Star Trek ever pondered the questions of 'cannister birth' so noticeable in Lois McMaster Bujold's novels?