1) Check ::1-X, where X is a larger number {1000,…}

To make networks more organized network admins have been caught numbering their hosts sequentially. While these numbers are essentially worthless without reverse DNS they make administration easy, and scanning easier!

2) Check ::X:p, ::p, where X is a large number {1,2,3,..}, and p is a common port {80,443,22,23,445,3389, etc}

Again, same reasoning as above. Network admins want to make Ipv6 maintainable and using a simple networking scheme makes network and firewall management more convenient. One major IPv6 deployment is guilty of using this strategy.

3) Check ::X:Y, where X and Y are in the set of english, leet-speak words that can be spelled in hexadecimal format.

Dead beef, b00b, babe, all abound in this namespace.