Please consider adding a new frontline mode where you can do battle with 16 npcs.
This will solve many potential problems with the current que system.

I propose a format where a team of eight does battle with 16 npcs. You could even make it so half of a given team will keep hitting ice as they get slaughtered and the other have kite around to make it a more realistic gameplay experience. Maybe have a few nin hide around bases too, teams of 5 pld, have the opposing npcs fight each other, ect...
Also you should make this format count towards mounts and hand of mercy titles, so it wont be a waste of time for those interested. Maybe even have a leader board where top amounts of kills are shown or post highlights of a large amount of kills to showcase top players.