AS YOU KNOW, will forever and always be a maximalist, in décor and otherwise, [but especially the former], but can be convinced, from time to time, to pare things down, just a little.  As a rule, modern elements can only be added to a space if the walls and floors and the very bones are already ornate, as in this Paris apartment — crown mouldings and carved marble fireplaces, warm chevron floors and gilded mirrors — only then, can the graphic and clean lines of modernity be allowed to enter and create what is fondly known here, as ornate austerity . . .