Nothing stops you using site- or link-local addresses and NATing to a single (or several) public IPv6 addresses, just as you do with IPv4. There was no "removal of NAT", it's just not necessary any more.
A proper firewall without NAT is generally fine, especially in combination with privacy extensions (which likely overall give better privacy than IPv4+NAT), but if you want to completely conceal the network layout behind your router, go nuts with NAT, no problem.
A proper firewall without NAT is generally fine, especially in combination with privacy extensions (which likely overall give better privacy than IPv4+NAT), but if you want to completely conceal the network layout behind your router, go nuts with NAT, no problem.