Renovation as the word suggest is about renewing. It should really be about the fabric of the buillding. Bringing it up to current standards of insulation, thermal and energy efficiency and so on, as opposed to restoration which is taking it back to or maintaining it's original state.
Roll top baths, exposed stone, beams and so on are more about interior design and decoration. They are really just a matter of fashion and taste.
As for, if you are designing for resale and therefore have a target market in mind, it is worth saying that there is a market amongst French buyers for Brit renovated properties, particularly amongst the more kind of Homes and Interiors style.