I always felt as if Oden was Sanji's parallel on the Roger pirates.
- Oden was the 3rd strongest
- Oden was a prince
- The way Oden chose to deal with the kaido situation all by himself without asking for help from the Roger or whitebeard pirates parallels Sanji at the beginning of whole cake island.
I feel as if Sanji will legitimately marry pudding, as a parallel to Oden x toki, sometime later in the series. They both actually like each other and I feel as if pudding will be extremely important later in the series due to her 3rd eye. Oda has also heavily hinted that the big mom pirates could be future allies with the whole o-lin thing, as well as the fact that Luffy has a friendly relationship with Katakuri, Pudding likes sanji, and the fact that Sanji basically saved the big mom pirates at the end of WCI.
Given how much the giants of elbaf hate big mom, I see blackbeard invading WCI and capturing big mom sometime after wano in order to deliver her to the giants and gain their alliance. I see elbaf partially being a big mom rescue arc where shanks, Luffy, and the big mom pirates ally to stop blackbeard. At that time, I could see Sanji marrying pudding in order to properly ally the big mom pirates with the straw hats.