Once you really get into IPv6 you tend to find that the addresses are not actually that bad or at least not as bad as you might expect. For starters, your prefix stays the same and probably looks like this 2001:wwww:xxxx::/48 ISP is wwww and your allocation is xxxx. There are lots of ways you can break up your allocation: yyzz. For me yy is the first dot1Q and zz is the second tag. yy = 00 is for single tagged 802.1Q VLANs. I have quite a lot of "spare" space for expansion, VPNs or whatever. So using the https://tools.ietf.org/html/rfc3849 documentation prefix 2001:DB8::/32 - that's my "ISP". Let's say I am :2d1:, I give my routers ::1 ie the first address and therefore on my default VLAN with no tags, I get an address of:
2001:db8:2d1::1 for the router on that VLAN (10.10.0.1)
My DNS servers are on a single tagged vlan 10 (they are 10.10.10.11 and 10.10.10.12):
2001:db8:2d1:a::11 and 2001:db8:2d1:a::12
I wont be using that site or anything like it. DNS does the trick for me along with documentation, just as it does for IPv4. I toyed with ULA addresses (a bit like RFC 1918) but dropped it because it adds complexity. You only need a few addresses to bootstrap a network and a change of ISP will have more hassles to deal with than a prefix change.
My old ISP gave me only a /64. That's absolutely useless for doing anything more than there most basic of configuration. This seemed to be because of limitations in their own infrastructure as they were using 6rd. I ended up switching ISP's to one that gave me a /48.
I seem to recall general recommendations that ISP's assign at least /56 to customers?
/48 for work (actually I have six of the bloody things!) and /56 for home which is reasonable. /64 is ridiculous unless they will give you more on request but then why not /56 so you can plan. We really are not going to run out of those and even /48 for all is pretty reasonable. At work I have an additional /64 just for WAN but I understand /112 and the like are popular for that as well.
I suggest you have a play with the /64 just for fun and to get the hang of things but the future has a shed load of IoT in it and all networks will need breaking up into subnets for security, including residential networks. Even if only to separate guest wifi.
In the UK we have the relative luxury of being able to choose from a fairly long list of ISPs. Some of them nearly get IPv6. Funnily enough dear old BT (business) is one of the few that gets it all correct out of the box, when you order a leased line.
When you see an IPv6 address mentally block out the last 64 bits. A /64 in IPv6 land is the equivelent of a single public IPv4 address for most practical purposes.
Back in the 80s or possibly 90s that might have worked, but an experienced admin today will look at a /24 and go "I can support 16 sites with that", whereas a /64 is really the smallest allocation you should see with IPv6, like a single IP address in IPv4.
2001:db8:2d1::1 for the router on that VLAN (10.10.0.1)
My DNS servers are on a single tagged vlan 10 (they are 10.10.10.11 and 10.10.10.12):
2001:db8:2d1:a::11 and 2001:db8:2d1:a::12
I wont be using that site or anything like it. DNS does the trick for me along with documentation, just as it does for IPv4. I toyed with ULA addresses (a bit like RFC 1918) but dropped it because it adds complexity. You only need a few addresses to bootstrap a network and a change of ISP will have more hassles to deal with than a prefix change.