Chromium plating is hardly a 'modern day' finish, indeed the few bits of britework on the Comp models were chrome plated. But not the hubs. If anything has improved, it is the durability and choice in paints. Chrome plating itself is not a durable finish, being rather porous to moisture unless underplated by nickle. And too, the preparation before plating needs to be perfect, as plating does not permit covering up of blemishes, unless a layer of copper plate is laid down for the purpose of polishing. Beyond that, the only option is to grind away at the base metal to create a satisfactory surface for plating.
At least with ambient temperature cured paint, you have the option of filling in the pitting, though if severe, some thought should be given to the soundness of the component for continued service. I do not like grinding away of the parent metal; I like to conserve what is there. After removal of the rust, I like to use an epoxy primer, as it can be laid on heavy and cut back to fill in the pits, and once cured does not shrink any further.
All in all, beside spending a lot of time preparing, and expense with the electroplater, chrome plating items that were not originally finished as such is not restoration but 'tarting it up' or individualizing it to suit one's tastes in style. And with the paints availible now, there is no need to compromise performance or durability.
If you go ahead and plate the brake drums, keep in mind one of the properties of chromium electroplate is a very low coefficient of friction... Also parts under significant stress need to be baked immediately after plating to prevent hydrogen embrittlment.
-Doug