- A reminder that Ethernet doesn't do broadcast, only multicast. (And L2 switching is broken by design anyway, but that's a story of hysterical raisins for another day)
- network names have been steadily been getting better with mDNS and related tech
- SSDP (the tech underlying UPNP) already covers IPv6, there's no need to add new one (your bigger possible issue is incomplete implementation on v6 side on CPEs)
- home router/CPE vendors are converging on "standard v6 default firewall" ruleset (it's actually something I encountered in random bought AP/router combos from random electronics store, not something techie-oriented). It establishes basic filtering that resembles what people think they get from NAT, and couples well with UPNP's support for IPv6. This also includes proper handling of ICMPv6
- subnetting is a problem, yes. Especially due to SLAAC vs DHCPv6 issues in some OSes.
It's not all nice, but it's getting there.
- network names have been steadily been getting better with mDNS and related tech
- SSDP (the tech underlying UPNP) already covers IPv6, there's no need to add new one (your bigger possible issue is incomplete implementation on v6 side on CPEs)
- home router/CPE vendors are converging on "standard v6 default firewall" ruleset (it's actually something I encountered in random bought AP/router combos from random electronics store, not something techie-oriented). It establishes basic filtering that resembles what people think they get from NAT, and couples well with UPNP's support for IPv6. This also includes proper handling of ICMPv6
- subnetting is a problem, yes. Especially due to SLAAC vs DHCPv6 issues in some OSes.
It's not all nice, but it's getting there.