People talk about the difference in Kid and Law's yonko fights, but the real difference in portrayal is between Shanks and Teach.
The thing about Kid and Law is that unlike say, Zoro and Sanji, the two literally have the exact same skillset. They both have strong DFs with DF awakening. Its just that Law's DF is stronger and Oda tends to favor him more because popularity. Which is why the whole Law being wildly stronger than Kid agenda never made sense.
But this absolutely isn't the case for Shanks and Teach. Shanks objectively has the better fighting style, Roger's swordsmanship with advanced haki. Teach has shown zero advanced haki skills. Meanwhile Shanks has shown all of them: future sight, ACoC, and internal destruction CoA.
Ultimately, I think portrayal sets up Shanks to be Luffy's final obstacle to PK more so than Teach for the aforementioned reasons. We even had that panel in PH where Luffy said he wants to beat Shanks, but doesn't want to fight him first, which lends itself to this idea. My guess is that Elbaf will be Luffy vs Blackbeard and Lodestar will be a Davy Back Fight between the SHs and the RHP, which will ultimately culminate with Luffy 1v1ing Shanks, allowing him to keep the straw hat.
