One Piece is not Naruto.
It was designed in EVERY WAYS to be a single closed story.
There is no "going beyond". UNLESS there is a spin Off but it won't be One Piece anymore and there will likely won't be the strawhats anymore.
That's right pal. One Piece after the timeskip has never been as good as it was before the timeskip, with Fishman Island, Punk Hazard and Dressrosa all having their own issues but the Yonko saga truly saw a decline in quality of the writing, starting during the second half of WCI right after the Tamatebakko box explosion, with the arc going off the rails after that.
And even WCI paled compared to Wano arc which is without a doubt the worst arc in One Piece so far, for the reasons already mentioned with its too long length, horrible pacing, the grievous lack of tension and stakes with too much plot armor and PIS to make it feel like the Straw Hats and their allies were really in danger; too much focus given to several side characters who were either boring or terrible such as Tama, Momonosuke, the Scabbards, Oden and Yamato; the terrible use and treatment of the Beast Pirates and even more horrible writing and treatment of Big Mom, lazy plot devices such as BM's amnesia or the waterfall; an ending after Onigashima that was ironically and paradoxally rushed compared to the slowness and stalling of the rest of the arc, etc...
And it doesn't look like Oda learned from his errors and decided to correct them with Egghead arc. It doesn't bode too well for the next arcs.