Note that a potential issue with that is IPv6. From all thrones listed by my node currently, all with IPv6 address belong to the same /64. It depends on the hosting company, but AFAIK, it would fit well to the design of IPv6 if a hosting company provided individual customers with such a range to use by default. In other words, with IPv6 you can quite probably run multiple thrones on a single VPS, which somewhat defeats the purpose of having a diverse set of masternodes.
Not sure I see the issue here. IPv6 is how things are moving, although it will take some time for adoption in the US. With IPv6 each device (a vps in this instance) is allocated a single address. Each IPv6 address is a public address, as the specification with IPv6 is there are no private addresses. Enough addresses for every device in the world, multiple times over.
Also, while they may be in the same block, the location is not known as there is no geo-location on IPv6. Many hosts offering IPv6 use a single tunnel for the traffic which is why you see this.
I'm not an expert here, but I think that the "routable" part of IPv6 is only up to /64 (i. e., half the full address). Of course, it is still up to hosters to actually dispense addresses and implement routing in their own network - but it definitely is not true anymore that a single VPS always gets only a single IP, and that extra IPs cost money. I just looked at the documentation for OVH as example, and it seems to indicate that each customer automatically gets a full /64 in IPv6 space (see
http://help.ovh.com/Ipv4Ipv6).
Note that I'm not necessarily saying that something needs (or can) be done here, just wanted to point that out.