I would be totally on board with using FreeBSD as my primary server OS .. if it had a container engine. There was a port of Docker to FreeBSD, but it's ancient and unmaintained (before Docker did their big modular refactor).
In theory, you could implement a lot of the Docker Engine API for FreeBSD and on the backend use jails instead of namespaces/cgroups and ZFS if you wanted implement the same layering. Some of the security and cgroup limits may not be implementable on FreeBSD, but with the Linux binary emulation layer, you should still be able to run a lot of containers without modification (unless they need certain filecaps or privileges).
I had OpenBSD on a laptop once, but without 802.11ac support, you'll either have to downgrade the Wi-Fi card in newer laptops or use a USB adapter.
In theory, you could implement a lot of the Docker Engine API for FreeBSD and on the backend use jails instead of namespaces/cgroups and ZFS if you wanted implement the same layering. Some of the security and cgroup limits may not be implementable on FreeBSD, but with the Linux binary emulation layer, you should still be able to run a lot of containers without modification (unless they need certain filecaps or privileges).
I had OpenBSD on a laptop once, but without 802.11ac support, you'll either have to downgrade the Wi-Fi card in newer laptops or use a USB adapter.