Hoot - Partridge "distrusted" the "portside out, starboard home" idea for "Posh" and gives other suggestions. He also comments on the Romani "posh" as in "half" (posh-horri = halfpenny and posh-koorona = half-crown).
Achmelvich - I go along with your idea that financial success can affect creativity, though not in all cases, and here I am thinking especially of Picasso. He was certainly well-off when he created "Guernica", one of the greatest paintings ever made.