My "TL;DR" reaction to this chapter: "Lol ok."
While I was never won over by Yamato as a character and, unlike my sheer joy when Jimbei returned, felt completely apathetic about him joining--other than hoping he would drop the Oden schtick--this still feels like a silly ending for him that makes me wonder what the point was of his whole character. To double down on the Oden cosplay to the point of trying to replicate his life and experience 1-for-1? Gag. But then again, there are a lot of things in this arc that felt like they didn't really pay off or have much purpose in the end (most of Act 2, anyone?), so I guess Yamato's just one more to add to the pile.
Also gotta say: what is with this weird thing of trying to push Law as "totally definitely Luffy's rival now for real!"? Like, Luffy has had way more of a "rival" dynamic with Kid all this time, so the whole attempt at "Luffy and Law and Kid are three-way-rivals and equals like they originally were at Sabaody" is just not really believable after Luffy and Law have been allies for nearly 400 chapters (almost 40% of the entire story by now) and acted more like vitriolic friends when it was just the two of them around without Kid. And hell, it's not even just Law; I always kinda liked that One Piece averted the whole "stock Shonen rival" thing by having the closest thing to a rival for Luffy be his main enemy Blackbeard, so trying to force this whole rivalry thing now with even Kid, let alone Law, this late in the story just feels hard to take seriously. Meh, sure, whatever.
So, with this end chapter, I guess one thing I can say is: at least this arc was consistent! As in, this was a pretty "blegh" ending to a messy, pretty "blegh" arc.