[nybble41]

> A lot of times people use IPs because DNS is not available or is more complex to set up.

For the rare cases where a memorized IPv4 address was reasonable you should just assign simple IPv6 addresses ending in a short suffix like ::1. The prefix can be 64 bits or less, which isn't too much to remember, and will be the same for the entire network.

> For example, I can remember some network prefixes and know whether they are in building A or building B. IPv6 makes that much, much more difficult.

Nothing prevents you from assigning visually distinctive prefixes to different buildings. The larger address space actually makes this much easier. For example, you could use xxxx:yyyy:zzzz:a::/64 for every host in building A.