There’s still a learning curve, but this approach addresses your items A, B, C and D above by allowing code to be developed and maintained in Java, with much less attention required toward accomodating the various browsers and their quirks.

GWT renders less relevant the skills of a Web site developer in overcoming browser quirks, and moves the UI away from hand-coded HTML and toward libraries of pre-programmed widget objects. CSS is still important, and would be an advantage for someone with a Web development background over someone with OOP native app development skills. But CSS is a lot easier to learn than OOA/D/P.