cheesefather, I just added this and will be monitoring its behavior over the next few days.
I agree with improper admin username being good functionality. I understand that too many people don’t change their admin username in WordPress (not very intelligent, but oh well….) In my case, I did change it and I too have the same situation as fratony while traveling.
If someone is security conscious enough to be using your plugin, one would hope that they change their admin username from admin! /;-{D Give it a thought about adding it in.
BTW, at first glance, this looks to be an excellent plugin.