Im gonna assume that your talking about Galleon, in his case Blizzard has already stated they learned a lot from him not only is he zergable but he spawns in a already crowded zone.
I expect the next world boss wont be in a heavy zone or zergable and you wont be able to use the current tag mechanic which leads to more crowding in a single location.
They also said the next world boss may have chance to spawn in multiple locations instead of one.