For me, most of the potential SHP vs. BBP match-ups are clear: Luffy vs. Teach, Zoro vs. Shiryu, Nami vs. Devon, Usopp vs. Augur, Chopper vs. Doc Q (and Stronger), Franky vs. Wolf, and Jinbe vs. Burgess.
Sanji vs. Pizarro:
- A former North Blue prince vs. a former North Blue king
- "Mr. Prince" vs. the "Corrupt King"
- Zoro, the counterpart Wing, will be facing Shiryu, who has a DF that Sanji has already overcome. Similarly, Pizarro's DF closely resembles Pica's, which Zoro has already defeated. However, in both cases, the challenge will be greater, either through Awakening or simply a stronger version of the fruit.
I think Lafitte is more likely to be matched with either Robin or Brook, since all three originate from the West Blue. Design-wise, he fits Brook. They're both lanky and pale and carry a cane. Brook served a West Blue kingdom as the leader of a battle convoy, while Lafitte was dishonorably exiled from his position as a sheriff. You can see the contrast here.