Well, the part about you being a fundamentalist Christian three years ago is damned impressive and does a lot to convince me that you're moving at a reasonable clip.
On the other hand, a good metaethical answer to the question "What sort of stuff is morality made out of?" is essentially a matter of resolving confusion; and people can get stuck on confusions for decades, or they can breeze past confusions in seconds. Comprehending the most confusing secrets of the universe is more like realigning your car's wheels than like finding the Lost Ark. I'm not entirely sure what to do about the partial failure of the metaethics sequence, or what to do about the fact that it failed for you in particular. But it does sound like you're setting out to heroically resolve confusions that, um, I kinda already resolved, and then wrote up, and then only some people got the writeup... but it doesn't seem like the sort of thing where you spending years working on it is a good idea. 15 years to a piece of paper with the correct answer written on it is for solving really confusing problems from scratch; it doesn't seem like a good amount of time for absorbing someone else's solution. If you plan to do something interesting with your life requiring correct metaethics then maybe we should have a Skype videocall or even an in-person meeting at some point.
The main open moral question SIAI actually does need a concrete answer to is "How exactly does one go about construing an extrapolated volition from the giant mess that is a human mind?", which takes good metaethics as a background assumption but is fundamentally a moral question rather than a metaethical one. On the other hand, I think we've basically got covered "What sort of stuff is this mysterious rightness?"
What did you think of the free will sequence as a template for doing naturalistic cognitive philosophy where the first question is always "What algorithm feels from the inside like my philosophical intutions?"
Barring a major collapse of human civilization (due to nuclear war, asteroid impact, etc.), many experts expect the intelligence explosion Singularity to occur within 50-200 years.
That fact means that many philosophical problems, about which philosophers have argued for millennia, are suddenly very urgent.
Those concerned with the fate of the galaxy must say to the philosophers: "Too slow! Stop screwing around with transcendental ethics and qualitative epistemologies! Start thinking with the precision of an AI researcher and solve these problems!"
If a near-future AI will determine the fate of the galaxy, we need to figure out what values we ought to give it. Should it ensure animal welfare? Is growing the human population a good thing?
But those are questions of applied ethics. More fundamental are the questions about which normative ethics to give the AI: How would the AI decide if animal welfare or large human populations were good? What rulebook should it use to answer novel moral questions that arise in the future?
But even more fundamental are the questions of meta-ethics. What do moral terms mean? Do moral facts exist? What justifies one normative rulebook over the other?
The answers to these meta-ethical questions will determine the answers to the questions of normative ethics, which, if we are successful in planning the intelligence explosion, will determine the fate of the galaxy.
Eliezer Yudkowsky has put forward one meta-ethical theory, which informs his plan for Friendly AI: Coherent Extrapolated Volition. But what if that meta-ethical theory is wrong? The galaxy is at stake.
Princeton philosopher Richard Chappell worries about how Eliezer's meta-ethical theory depends on rigid designation, which in this context may amount to something like a semantic "trick." Previously and independently, an Oxford philosopher expressed the same worry to me in private.
Eliezer's theory also employs something like the method of reflective equilibrium, about which there are many grave concerns from Eliezer's fellow naturalists, including Richard Brandt, Richard Hare, Robert Cummins, Stephen Stich, and others.
My point is not to beat up on Eliezer's meta-ethical views. I don't even know if they're wrong. Eliezer is wickedly smart. He is highly trained in the skills of overcoming biases and properly proportioning beliefs to the evidence. He thinks with the precision of an AI researcher. In my opinion, that gives him large advantages over most philosophers. When Eliezer states and defends a particular view, I take that as significant Bayesian evidence for reforming my beliefs.
Rather, my point is that we need lots of smart people working on these meta-ethical questions. We need to solve these problems, and quickly. The universe will not wait for the pace of traditional philosophy to catch up.