After reading all of these, I think what is most important is what is most comfortable for a GL.
Do you like small spurts of action throughout the con? Then tweet your locations constantly and limit your challengers.
Do you like battling in long sessions? Then find a place to camp out and take as many as you can.
Do you like keeping track of queues? Then do it. Don't? Then make the people waiting do it.
All of these things have had positive results. The important thing is that you not only stick with your method and be respectful to others about your expectations.
When I had to cut out because the challengers I was going to battle were actually battling each other, i made sure to find another GL (Thanks again, Cyrus!) to cover for me.
You make it work the best you can.
Not every challenger is going to be happy with you, no matter how hard we may try.
And sometimes challengers are dicks.
Just do your best.