I would recommend stainless hardware as long as the strength is equal or exceeds the strength of the original hardware. I use a lot of stainless steel hardware on my vehicles, as I have a good supplier of high strength stainless hardware. And it looks almost as good as chrome, but doesn't corrode.Zinc is the metal used to make sacrificial anodes for marine applications because it corrodes at a predictable rate, and much faster than copper or lead in a marine environment. I'm curious if it would be better to use stainless bolts in coastal areas, or if it would further complificate things to change the chemistry.
But I still use a non-corrosive agent of some type to make sure that dissimilar metals, and especially electrical connections, power and ground circuits, to prevent future corrosion issues. It's just cheap insurance.