i want to document my doubt here. luffy will say "screw it" and go to elbaf anyway. law is going to hachinosu, kid is going to elbaf.
there is no poneglyph on sphinx island. bb probably has the last one. weevil won't be defeated, bakkin is the 10th titanic captain, his story won't end yet.
it makes most sense to me that bb's island is the farthest out. the one closest to lodestar. elbaf will me analogous to sabaody, in that analogy pirate island is marineford. a dangeorus hq that is in the way.