Basically there has been almost no dynamic in the post timeskip.
Lol people really think this
It pretty much falls to whether you like one more than the other, which could be a million of your own reasons. But since we're talking about a serial, we're talking about a unique advantage for later material: addition. If the relationship between Zoro and Robin stops developing, you can say it's been replaced but not deleted or regressed. All of the old relationships are there, many are still being developed, and many dynamics are new. I mentioned Robin twice already and in one case her relationship with Jinbe, but let's look at another he already has going:
Fire and water, punches and kicks, cook and fish. I'm sure Oda didn't deliberately try making this work.
And for another mention of Sanji:
Let's look at another old one intensified:
Check the parallels thread and others, these two are more of a duo than ever. The plot simply wasn't big enough pre timeskip to have Luffy and Zoro side by side as frequently, and yet they couldn't really get the distance between them to miss each other or catch up.
Speaking of falling back into place, Chopper is in the mix but Nami and Usopp have had a special relationship since East Blue. It was so good how Oda brought this to the front of the reunion because the truth of the narrative is that they can't help it.
I mean even when you pick two names out of a hat, there's something that builds on the past. Like when you think of Nami and Robin past similarities and how they handled the crew respectively in Arlong Park and Enies Lobby, becoming a pair of castle spies only makes sense
New development on the other hand: Brook is a clutch assist
And bringing it back to Sanji for one last point, you'd better believe that Usopp and Chopper (as well as Luffy and Franky) have something to say when the dude gets a Sentai upgrade:
Long live the boyish side of the crew
And to Sanji's credit, we just had him smiling about how Franky would like those repeating lasers.
Going back to the idea of addition, Law in that Raid Suit part is added without changing the fact that this is the Sea Train trio dynamic. You don't have to know or recognize that, but Oda has that in their history for reference because that's just how stories build.