I was friends with a priest who was in Mensa in Washington D.C. who was a big Jesus seminar guy. We had many discussions on this topic. Your critiques sounds similar.
https://en.wikipedia.org/wiki/Jesus_Seminar
...The Seminar treats the
canonical gospels as historical sources that represent Jesus' actual words and deeds as well as elaborations of the
early Christian community and of the
gospel authors. The Fellows placed the
burden of proof on those who advocate any passage's historicity. Unconcerned with
canonical boundaries, they asserted that the
Gospel of Thomas may have more authentic material than the
Gospel of John.
[8]
The Seminar holds a number of premises or "
scholarly wisdom" about Jesus when critically approaching the gospels. They act on the premise that Jesus did not hold an
apocalyptic worldview, an opinion that is controversial in mainstream
scholarly studies of Jesus.
[9][
need quotation to verify] The fellows argue that the authentic words of Jesus, rather than revealing an apocalyptic
eschatology which instructs his
disciples to prepare for the
end of the world, indicate that he preached a
sapiential eschatology, which encourages all of God's children to
repair the world.
[10][11]
The method and conclusions of the Jesus Seminar have come under harsh criticism by some[
quantify] biblical scholars, historians and clergy for a variety of reasons. Such critics assert (for example) that the Fellows of the Seminar are not all trained scholars, that their voting technique doesn't allow for nuance, that they are preoccupied with
Q and the
Gospel of Thomas but omit material in other sources such as the
Gospel of the Hebrews, and that they rely excessively on the
criterion of embarrassment.
[8][12][13][14]
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My critique of the seminar is and was that the criterion on embarrassment is weak copy of the idea of declarations against interest. But, the converse of a DAI should not be discounted.
If you start you critique overweighting declarations against interest you have no reason to expect an accurate weighting of the remarks of a truthful person.
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Since you obviously put some time into your philosophy, I would like to hear more about your idea of what the gospel and salvation really is.