To: "whynot".
You posit that the two moral imperatives of life are:
1. To live as long as possible
and/or
2. To create/discover/build a life one can live with (in laymen's terms: to be happy)
I can only partially follow your following arguments because they are, to my simple mind, written using an unnecessary amount of jargon which tends to mask your basic points.
But I have to say that I disagree with your two imperatives, as I understand them.
Surely, if there is an underlying principle behind all moral decisions in life, it must be the desire to pass on our genes?
Parents are willing to sacrifice their lives for their children.
We want to live for a long time because people who don't tend to have fewer offspring and so don't tend to pass this tendency on to the next generation.
There are other objection to your first imperative, but I believe they are superficial. For example: suicide bombers. They clearly do not want to live as long as possible.
But I would say that, in a sense, they do. It's just that they sincerely believe in a life after death and they believe that their actions in this life will result in a more comfortable afterlife (in paradise). They are therefore, in a strange way, conforming to imperative number 2.