In my experience IPv6 is much simpler to deal with than IPv4; in fact the large address space with a 64-bit prefix as the network number greatly simplifies management and configuration and theoretically improves the CPU performance of routers by allowing allowing more aggressive route aggregation. When ISPs give /56 prefixes to users, users can easily set up subnets according to their own needs without requiring extra coordination and without breaking end-to-end connectivity. You are wrong that /64 prefixes are usually assigned to a single host; in fact the number of Internet-connected devices in a typical home has grown over time and can easily be a dozen or more.

If I were running an ISP, I would migrate the backbone network to IPv6 and just use embedded IPv4 addresses to avoid the headaches that come with router-to-router IPv4 links. With IPv6 you always have a link-local address on every port that can be used by routing protocols without relying on proprietary solutions that are not interoperable between vendors or having to assign an IPv4 address (and hoping that you assigned a large enough subnet for future growth). It is much easier to scale up an IPv6-only network and much easier to connect one IPv6-only network to another.

Of course IPv6 is not perfect. SLAAC did not really work out as planned and now we are stuck with an annoying mix of SLAAC and DHCPv6. Reverse-DNS is still a bit of a pain. IPSec is not what it should have been and too many IPv6 standards rely on IPSec for security/authentication. Even so, the core of IPv6 is a huge improvement over IPv4 for individual users, small network operators, large network operators, and the Internet as a whole.