If I were building a new house, I’d make sure I hardwire as much as I could think to wire. The hard wiring sets the foundation for any smart home. While you can fine wireless technology for most things, hardwire contact sensors are better than wireless ones. Also hardwire ethernet to bedrooms and audio locations is a good idea. If you have young kids. they’ll be thankful you did when they get heavy into gaming. You can always fill in area’s you didn’t think about with wireless technology.
You need power for any camera, so Power Over Ethernet gives you better data transfer from the camera. You use the same ethernet cable for power and data. For outside camera’s you should also wire for a light source offset from the camera. If your light source is on the camera, you’ll get to watch spiders make webs all summer.
You might find this post on full house audio system useful.
By default, sensors put in place for a smart house give you most of what you need for a security system. This post gives some suggestion on setting up cellular as a backup for the security part of your system. One thing that is helpful is having your HA controller centrally located in the house, in case you decide to use zigbee or zwave for some devices. If you want the security system capabilities then you should also think about battery backup for devices you consider to be essential for security. This post gives some information on integrating hard wired contact sensors using GPIO pins on you controller board,