Making people wait at graveyard is not the best design, it is boring. Fast respawns, and keeping people engaged should be the goal.
Have charges/ hit points on the respawns and to recharge them, you have to capture/repair the graveyard in a flag encounter. Have a widening ring of respawns that chain farther away, so you have to run back, but the goal might be to get the respawns working closer in for the farther out teams to basically "save" the fight.
Have the respawn chains lead to a buff in the fight from a far away temple or something for more tactical options. Give Large guilds the carrot of the boss fight, but small guilds and individuals something to do to harass and or muddy up the fights.
Players drop a effort token on deaths in the area, that other players can grab, but the more deaths the more % of the tokens you drop.
Like the lantern seeds and such, gather em up during the event, die like a dumbass, for the 5th time, drop 50% of your tokens.