Okay. I think you're overcomplicating something that's supposed to be very simple, he's been one of the most straightforward characters from the beginning.
What indeed is interesting are Shanks' intentions. He never showed interest in being PK. To me it always seemed like he just wanted to be free, and have fun. But that same desire is what has driven Luffy to want to become pirate king. We could write that off to Luffy's misconception that the pirate king is the most free pirate in the world, while Shanks probably doesn't think the same since he's "smarter" than our hero?
We could say Kaido and BM showed a fair amount of ambition now. Whitebeard also didn't seem to care about being PK. So is the only reason Shanks became a Yonko being free and rampaging across the world? To me he seems exactly that. With addition of wanting that Roger's will lives on.
What indeed is interesting are Shanks' intentions. He never showed interest in being PK. To me it always seemed like he just wanted to be free, and have fun. But that same desire is what has driven Luffy to want to become pirate king. We could write that off to Luffy's misconception that the pirate king is the most free pirate in the world, while Shanks probably doesn't think the same since he's "smarter" than our hero?
We could say Kaido and BM showed a fair amount of ambition now. Whitebeard also didn't seem to care about being PK. So is the only reason Shanks became a Yonko being free and rampaging across the world? To me he seems exactly that. With addition of wanting that Roger's will lives on.
Someone like Blackbeard planned to increase his bounty to become a Shichibukai, in order to enter world government area's and break free 5 of the worst criminals he could find. That took hundreds of chapters to realize the purpose of his true goal and I am oversimplfying it. Kuma's entire motivation for becoming a Pacifista is a mystery. Doflamingo hinted as his underworld business hundreds of chapters before it was tackled. Crocodile wanted more than just to take over a country, it was tied to his interest in an ancient weapon.
This is not an "overcomplication" of Shanks character, im legitimately asking questions based in the mysteries Oda has set up, because that's exactly how it looks to m, same as it did for many other characters in this series. Shanks meeting Gorosei should be the biggest red flag people should notice now, and is a big detractor on him just being "good". Those men are evil and justifiably so. It was done with extreme purpose. Even the editor left a note "what IS this man doing here??" And that is just one of many things you can point out.
I'm just saying, with how Luffy refers to beating Shanks physically and with how Shanks looks at Luffy's bounties in an extremely imposing manner virtually every time, i would NOT be surprised if there is some underlying layer that pits them together. "Friendly competition" to me has never cut out as a true fight for Luffy, that's best left to Mihawk and Zoro. There would have to be a motivation that makes them fight.
I don't think any of this harms the narrative, in fact, I think it massively elevates it to something we haven't really seen before in Shonen: an actual, morally grey final antagonist.
I actually implore people to take this idea seriously, because it has been set up in a way where it makes sense and works. We know virtually nothing about Shanks' character, and I often compare this to someone like Dragon, who is just as enigmatic. The difference with Dragon is, you know what his army's goals are (we just don't know his motivation). There is truly nothing secret about that outside of Kuma's sacrifice. Its all there layed out by virtually good people, including Luffy's brother and Robin. But with Shanks, we cant even virtually say the same thing. Hes appeared more than Dragon, yet we know very little about what he wants with Luffy, what his goals are, why he's not interested in One Piece seemingly, why he meets with someone the RA is intending to defeat (which again, implies that the RA is virtually a good faction, while not really for Shanks) and much more. One has clearly defined goals (with a mysterious motivation), the other is entirely missing their goals and motivation.
If anything Rayleigh fits the description you mention over Shanks, and I think that's an important destinction. Luffy spent even more time with Rayleigh in that regard.
Time will answer this question