I think the general reaction on the rule book is, the thicker it is, the less useful it is, because you want people to make ethical decisions. The more you complicate life, you end up pretending you have perfect or almost perfect foreknowledge of all the permutations that can arise, and that you've got rules and sub-rules to deal with each one of them. Then it's more or less a mechanical process, expedited nowadays by using keywords, for example, and you find the right sub-sub-sub-rule for the extremely rare circumstance, that nevertheless, despite its rarity, you were able to anticipate.
You can tell from my involved sentence with long words, I don't think a lot more rules are necessary. I think that people operate better and more maturely when they're challenged to understand principles, and then go through enough iterations of applying those principles. We can look, for example, at the kinds of simulations that Mr. MacDonald talked about. They should be very rich simulations and not just a few sentences about “if this arises, what do you do; if that arises, what do you do”. They should be the sort of thing that a good playwright would give you in a one-act play. You do a lot of those, and then you become sophisticated in how to think of principles and ideals. Then you'll come up with the best possible answer.
It's a grey world, and it's not as if at the end of this somebody else has the correct answer and is going to check whether you got it or not. No, you have to have a really good answer and really plausible reasons why you brought it up, and somebody else has to do a darn fine job of coming up with a better scenario than you did.