I think the twist is a bit lame story wise. He has this godlike fruit, which of course, is bound to the creativity of the user, but it takes away something of the whole plot and magic about it. Trying to get the fruit for 800 years? Joyboy, who even Oden and Roger waited for? Comon. That's weak writing imo. It's a power up mixed with "the chosen one" and a very simple explanation for all of it. A fruit ...
But still, Oda, as genious as he is, made up for it with charme, the gear 5 looks and humour. Its not the first ridiculous power up in the story, given the fight with Rob L. etc.
But these were just build on will/ friendship/ promises and not some outer source. Let's see where this will lead and after 20 years of excellent work, why not.