User blog comment:Fliu/Typical Straw Hat moments/@comment-24850639-20160421210449/@comment-24769684-20160426205752

Big Mom is much too powerful for Luffy to defeat right now, especially with members of his crew who are medium-weak in power, since she should be at least at a similar level to Kaido. I think the main villains will be Daddy Vinsmoke and Germa 66, with Sanji's brothers possibly thrown into the mix. It would be the best way to get some insight into Sanji's past, as well as further destabilize the Underworld.

Big Mom might be left for later, but as I've said in the past, I kinda hope she allies with Luffy, since given how focused the narrative is on Kaido it would seem kinda weird to turn to her next like an afterthought. I actually think we'll be reaching the beginning of the end of the manga after Kaido is brought down, with the next part dealing with the effects of Reverie and wherever the fourth Road Poneglyph is.