This is rather difficult to discuss because you must think on behalf of every Server Owner that would use such a system (Such as Sprunk Buster). I'm fairly certain alot of owners would actually be against IP Range Banning due to the fact it may also ban innocents & then the possibility of the banned target finding a way around that ban anyways, so I don't recommend IP Range Bans for this reason...
However, single IP Banning alone wouldn't do very much as most IPs simply change. Banning a player by name alone isn't recommended either because there are alot of common names used by multiple players. But then of course could easily just be evading by simply changing the name. But what I can suggest is maybe comparing the IP Range of a Banned IP along with a matching Banned Name.
Either way though, I personally don't see the worth of scripting such a system due to its lack of effectiveness. It just seems the system would only block something like 10/100 Hackers. My ideal solution of handling hackers is completely diffirent though since it doesn't involve banning. However, it's not globally & might throw people off topic here, so I won't mention it.
Banning players who have been banned from a X amount of other servers isn't a bad thought, but the question would then be, how many 'Idiot' Server Owners who ban without proper reason use this system? Another idea regarding this system, perphaps giving the option of servers unbanning players as well. Although this might of already been installed or whatever, but just throwing that out there just in case.
Personally, would I ever use such a system for any of my server(s)? No, I don't think I would just for the fact that I feel I should deal with every hacker or whatever as they come. There is also the chance that some of these hackers realize thier mistakes & stop the cheating & in that case I would give them another chance etc.
These are just my opnions & views about such a system though, I still wish you the best of luck if you decide to follow through with it