Well, it would be great to be able to ban a netmask or a range of IP addresses...

Not only by using *.* but by supporting netmasks and ranges.

Like 192.192.192.0/15 etc...

or range 192.192-253.*.*

I don't see the point of this, personally.

If you wanted to block a whole providers subnet, it's going to be either a /24 or larger, making up several XXX.XXX.XXX.* blocks. Nice and easy.

If you need larger than that, you should really consider "Why am I blocking this big of a range". It's not really important to get as granular as XXX.XXX.XXX.1-15 as all network providers require a minimum announcement of /24.

Perhaps your large blocks belong in htaccess?

Perhaps your large blocks belong in htaccess?

I would agree with this, I'd block these large IP blocks through your web server (or software firewall) if possible.