Yeah well. I'm not sure if this is possible. I mean, it's possible, but people with ping will have to queue for like 10 minutes. But I totally agree with you. Sometimes I even think that they abuse their lag on purpose.
I don't know if this would make things a whole lot better for people with high ping to get into duels faster, but what if the people with higher ping have priority to get into duels. For example say there are two people waiting in queue to get into duels. One guy has low ping and the other has higher. The two people in queue can't fight each other because their ping doesn't match each others "Maximum Ping Difference". Then a third guy joins the queue that matches both the two first players settings. The third guy would then always fight the person with higher ping because people with higher ping have priority.
This would make balancing different pings at least a little better.