My next project, IPv6 in my homelab. It will be a challenge but it is time. My ISP gives me a static /48, I should use it.
The most difficult parts for a homelab in my experience is getting Docker to play nicely. All of the other stuff sort of just works these days. Even things like using DHCPv6 prefix delegation to obtain a routable subnet is almost trivial with how well-supported the protocol is with modern networking software.
https://ipv6.he.net/certification/ has instructions on how to get started.