The best defence of the "reappraiser" position is to be found in Br Tobias Haller's "Sex Articles". For all their protests, none of the "anti" crowd have ever come up with anything nearly as sophisticated, and his points remain unrefuted .
Because of the density of his work, however, I have come up with my own cheat sheet to remind me why (lest I become complacent and take my position for granted) I regard the classic Christian position on homosexuality as untenable. Here they are:
*Because St Paul had no concept of an innate "homosexual" orientation (hence my double invert commas: it's an anachronism). You can't try to stretch what he says to fit a topic he wasn't writing about.
*Because St Paul was fallible. He was only the human instrument of divine inspiration.
*Because the Greek of the passages in question, to the extent that it is intelligible at all, seems to refer to specific forms of "homosexual" activity that we wouldn't recognise today.
*Because each of the passages in St Paul comes in the context of a broader rhetorical argument of which "homosexuality" is not the point. It's used as an example of depravity, one which would not have been questioned in that time and place.
*Because St Paul in general does not express a recognisably Christian ethic of marriage and sexuality. It's laughable—and incoherent—that so many who profess to believe in the sanctity of marriage (or rather, some marriages) take their cue on homosexuality from a man who didn't believe in that sanctity ("It's better to marry than to be aflame with passion," remember?)
*Because Jesus himself reduced the Law to a bare minimum expressed in the Summary of the Law and the Golden Rule.