In New England, and I'm assuming that's what we are taking about, old houses are the norm. look around the neighborhood and if it's an old one full of beautiful old homes then if the #s work then yeah I would say it's worth it all day long. In my experience as a contractor the trend is restoration of old homes with the addition of modern amenities is what more affluent people are wanting. The old workmanship is way above and beyond what is being done today and people will pay a premium for that. One thing that will forever kill an old house is the removal of such details. It costs money to do this, more than just gutting and putting big box garbage everywhere but like I said, people will pay for it as long as the house is solid and the updates to electric, plumbing and hvac have been done. If one tries to turn a house into a McMansion in a neighborhood full of original Victorians the neighbors will try to block it and buyers will walk. It really comes down to #s and location.