Yeah IPv6 has some pretty sweet innovations baked in. More efficient packets and routing, reduced performance hit by oversized broadcast domains, etc. But potentially problematically it technically does not allow for NAT so every computer has a publicly routable IP address. It does however have a very nice system for link-local networks.

I think the biggest brainfuck for IPv6 is managing a dual stack network because you end up translating concepts between IPv4 and IPv6 that really aren't meant to be translated