Thanks for your kind words! I do my best to be as clear and understandable as possible.
Concerning your question, yes it is possible to apply NAT to unique local IPv6 addresses and translate them to global unicast addresses. In order to do so we would employ NAT66, that is Network Address Translation IPv6 to IPv6. This functions exactly the same way as NAT for IPv4, by translating the IPv6 address as well as manipulating the transport layer ports in order to allow PAT. Now although this is possible, it is not very desirable as you stated as well, because we have the appropriate address space to assign each and every internal device with a global unicast address. However, a better alternative to NAT66 is NPTv6.
IPv6-to-IPv6 Network Prefix Translation or NPTv6 isa feature that allows for the translation of IPv6 addresses from one subnet to another without the requirement to rewrite the transport layer headers. This readuces the load on network devices and also does not interfere with the encryption of the full IP payload. This is a huge improvement to traditional NAT because it avoids many of the problems that NAT traditionally introduced into networking. To find out more about NPTv6 take a look at the following Cisco link.
Essentially, the use of these addresses is that you are free to use them on any internal network without the need to for centralised registration. If you start using global unicast addresses on your devices and you allow them to connect directly to the Internet, (without any kind of translation mechanisms) the local ISP will not necessarily route those addresses because they are not registered to you. You can still use them if you use a translation mechanism so the actual address doesn’t appear on the Internet itself, but what if your destination on the Internet just happens to be the same as the IPv6 address you gave to a host on your network (highly unlikely, but possible nonetheless). By using the unique local addresses with a translation mechanism such as NPTv6, you can assign addresses internally as you like while creating the appropriate translation to get on the Internet without fear of conflicting addresses.
I hope this has been helpful!