[gertrunde]

I'm not sure it's that much more complicated as such, beyond being different/unfamiliar.

Just setting up SLAAC is very straightforward, probably (ignoring any unfamiliarity issues) more simple than DHCP?

Pulling addresses from your service provider via prefix delegation can be a bit funny, and could do with being a lot more polished. Instructions/community support in particular can be problematic as ISPs tend to use different prefix lengths, rather than just standardising on /56. And also less relevant if you have a static allocation, which is potentially more likely with IPv6 than IPv4.

And DNS becomes more important, as does firewalling, no more relying on the somewhat dubious NAT safety net.