@AvocadoInTheRain:
It serves to tell an interesting story that Oda hasn't told before.
You think that an author like Oda thinks that Pound sacrificing his life while nobody realizes his existence or motivations is an interesting story he likes? Oda? The guy who quit Fist of the North Star as a kid because his favorite character died and keeps bringing characters back from the dead for the most asinine of reasons for over a decade to make sure everybody's favorite character in present-time still lives. Pound sacrificing himself like that would maybe work in a flashback, but not in present time. No way.
It also wraps up his character. It would take an awful lot of time in Elbaf for Oda to develop the relationship between him and his daughters (and grandson) and have it be meaningful. Of all the many plot threads from WCI left open for later, I don't think this one is too high up on the list of things people want to see. There's no Pound fanclub and if Oda's editors are any good it would get axed for panel-space.
I don't think it would take much time at all. The family just has to meet, talk a little, and cry. He only needs a third of a chapter for that. All of the build-up to why they would care about meeting each other is already there. Pound wants to see his family again. Chiffon will get emotional because she will realize Pound saved her and Petz' life and she had a parent who actually cared about her wellbeing all along. Just have them meet and boom, done. Oda just needs to set up the necessary coincidences to connect the pieces. The only complicated part in this is digging up a reason for why Chiffon would be at Elbaf since she is with Bege and they have no interest to either see the Big Mom Pirates again or go to Elbaf. But it's Oda. He'll make up some contrivance as the story progresses.
We're getting closer to the end of One Piece. Oda needs to start tying up all the loose ends he's left throughout the years. He can't go creating too many of them after each arc anymore.
He will make as many as he wants because his creativity is out of control no matter how much he restrains himself lol. And this is somehow implying Pound is not a loose end that should be solved. Pound's fan popularity does not matter. If he didn't matter, he could have just stayed in the Seducing Woods. But no, Oda wanted to bring him back so he could save his family from Oven at Cacao Island. He's going somewhere with that guy and he is not having three or more permanent arc deaths. Especially when, unlike Pedro, no one has talked about him after his sacrifice to give him proper respect and mourning. That is what Oda does for his "good" characters.
Two cover stories that take place about a week and a half apart in-universe. You're expecting me to believe that Lola makes it from Water 7 to Shanks' territory in the new world in that amount of time? What is she doing hanging around in Water 7 bars if she's getting married in the new world so soon after? Getting married has been her one driving motivation, you'd think she'd try not to be almost completely across the world from the groom.
That just makes zero sense.
It makes as much sense as it has to for Oda's convenience. The Red Hair Pirates travel around too, they're never stuck at one place. If they can go to East Blue on a whim, if both Ace and Mihawk can find them, and if they can show up in the Marineford War supposedly unnoticed, then they can show up wherever Oda wants them to. She hung out in the Water 7 bar so that Oda could give a confirmation that she survived whatever spooky forces were around Thriller Bark and managed to make it to nearby land, and the previous arc before Thriller Bark is Water 7. As for getting married to Lucky Roo so soon, just have it be a shotgun wedding that might happen as fast as their fast meeting. The gag could even be that Lucky Roo says yes on a whim similar to Brook accepting Luffy's crew invitation. As for why lola wants to go back to the New World, who knows? Maybe she finally wants to patch things up with her mother, she misses her sister, or she thinks something silly like already asking out every man in the Grand Line and needing to try out another ocean.
After Mihawk chased down Krieg's fleet from the Grand Line to the Baratie and Rayleigh swam to Amazon Lily from Sabaody Archipelago, Oda will do whatever he wants to get characters where he wants them no matter the timeframe.
Here is what I do know for sure. That cover story with Shanks at the wedding was made during the Totland arc. An arc arc all about children being forced into political marriages to cement alliances. The arc where a big deal is made about Lola skipping out on the wedding a Yonko was looking forward to as the key to her piracy success. So it is very possible that Oda juxtaposes these stories together to plant seeds that seem individual but eventually connect (and maybe indicate how last-minute he planned all of this). And if the bride and groom were not shown, and the groom can be assumed to be the one missing Red Hair Pirate since that group only has men, then by process of elimination, the bride is probably going to be the only character in the series who cares about marriage and has recurring relevance. Sure, the bride could be a completely new character, but we have nowhere to go with how that connects to the main plot. So siding with the evidence and reasonable assumptions we can make is fine.