Yes electropolishing is better as it passivates the stainless and prevents corrosion. Every major area has a shop that works in stainless. I know a good one locally I have used for 20 years but there should be one close to you wherever you are.
I do not know of a current boat with the chainplates bolted to the cabintop. The Bayliner Bucaneers were done that way though in the 70s.
Living aboard in Victoria Harbour