Just wanted to spell out why central duct systems are a central part of ANY home design. Yes, ductless mini split heat pumps are awesome. Yes, radiant flooring is comfy. Yes, lots of people use decentralized HVAC strategies around the world and are happy with them (or at least they don't know what they're missing).
Duct systems can be used to filter and deliver healthy air to every room in the house- humidified/dehumidified, diluted with outdoor air, and pressure relieved for kitchen exhaust.
Learn more about designing ventilation and HVAC in general at: https://BuildingPerformanceWorkshop.com
Watch the first TV series about the Science of Homes: https://HomeDiagnosis.tv