I very much doubt that many people will be interested in all the great credentials. People like stuff like being able to turn the lights on and off using thier phones. Being able to turn the heating on when on the train. Turning the cooker on from the dest at work. People spending a lot of money on a house generally don't care about the EPC rating etc. One of the problems is that we have got it the wrong way around. Our smaller, cheaper, starter houses are what should be built to much higher standards. Loads of insulation, airtight, etc, are generally the one's that are badly built to minimum standards. If you want to sell for a bit of a premium, then look to add sexy, before practical.