I've been wanting to comment on this, but every day I get further behind on the required reading, so it's becoming hard. Let me put in a couple of less-than-well-thought-out words:
First, Glenn Reynolds may think he's mainstream, but he's not. His libertarian outlook gives him a strongly progressive view on science, more progressive than that of most scientists I know. Definitely more progressive than most of the general populace. Therefore, I have a hard time taking his worries about council stacking seriously, since I think balanced in his view is a far cry from balanced in most other views.
And that's really the question here. A balanced council is useful, but balanced in what sense? Balanced where? The council is meant to advise the President, and as such, it needs to share certain core assumptions with him. Anyone too far removed from the president's worldview would have difficulty giving him coherent advice. He wouldn't be starting at the same place.
Second, I am personally against embryo stem cell research. I think there is a danger here that embryonic human life will become a commodity, and that is a dangerous attitude. Moreover, there's reason to believe that adult stem cell research holds more promise, and I'm all in favor of that.
Third, many have taken great offense that Leon Kass has stated that greatly extending human life expectancy would decrease quality-of-life. Put aside the fact that immortality has long been a dream of humans everywhere, does anyone deny that this is true? We are already facing a runaway Social Security system because life expectancy has increased by ten years since its founding. What if it extended by another ten, or a hundred? While we work hard to prevent premature death, no one lives forever. The death rate is still 100%. I'm troubled that some people never question whether increasing human life expectancy is a good thing, that they insist that there is, in fact, a moral imperative to do so. Would we really be better off if we lived forever? Sure, I'd like to live an extra hundred years, but if I were given the opportunity, I wouldn't jump at it without considering the cost.