Charlotte Pudding could restore Kumas memories as she is able to extract and manipulate memories
and her DFs ability even allowed her to stimulate memories in homies of the people whose souls were used to create them.
All this could develop into a sidequest to rescue Pudding from Blackbeard...
There is still military commander-in-chief and former fleet admiral Kong (ch. 594) who is, at least politically, between Akainu and the Gorosei. But maybe Oda forgot about him. :3c
Don't you think it might be possible that the kingdom is named after the Mineral gypsum (or calcite) which was also called Alabaster in the Arab world and Egypt. There was even an ancient town in Egypt with the Greek name Alabastron. And some sarcophaguses are made of alabaster.
Coincidentally...