I look forward to reading your article, and I hope that I helped in some small way, but just to play devil's advocate, the 1875 head and the 1876 head are more similar than different.
Look at the reverses of the 1807 Capped Bust half and the 1891 Barber Half. One can reasonably argue that they are the same design with differences in inscriptions. At the other end of the difference scale, the two different $50 Half Union obverses are certainly the same design, even though they have slight differences in ornamentation.
Your opinion that the 1876 and 1877 designs are not "Sailor Heads" is a perfectly valid opinion, but others may have other opinions.