If we taboo and reduce, then the question of "...but is it good?" is out of place. The reply is: "Yes it is, because I just told you that's what I mean to communicate when I use the word-tool 'good' for this discussion. I'm not here to debate definitions; I'm here to get something done."

I just wanted to flag that a non-reductionist moral realist (like myself) is also "not here to debate definitions". See my post on The Importance of Implications. This is compatible with thinking well of the Open Question Argument, if we think we have an adequate grasp of some fundamental normative concept (be it 'good', 'reason', or 'ought' -- I lean towards 'reason', myself, such that to speak of a person's welfare is just to talk about what a sympathetic party has reason to desire for the person's sake).

Note that if we're right to consider some normative concepts to be conceptually primitive (not analytically reducible to non-normative concepts) then your practice of "tabooing" all normative vocabulary actually has the effect of depriving us of the conceptual tools necessary to even talk about the normative sphere. Consequent talk of people's (incl. God's) desires or dispositions is simply changing the subject, on this way of looking at things.

Out of interest: Will you be arguing anywhere in this sequence against non-reductionist moral realism? Or are you simply assuming its falsity from the start, and exploring the implications from there? (Even the latter, more modest project is of course worth pursing, but I personally would be more interested in the former.) Either way, it'd be good to be clear about this. (You could then skip the silly rhetoric about how what is not "is", must be "is not".)