Oda has messed with silhouettes before but damn I thought the silhouette looked more like Shiki than Gaban. Though Gaban makes more sense when you think that Shanks family is being discussed, SHPs are one RP away from LT and just now meet the navigator of RPs.
As for parallels, Ray is not 1:1 Zoro and Gaban wont be 1:1 with Sanji. Oda has preserved the M3 dynamic so far, that aint changing, so Sanji indeed has parallel to Gaban but Gaban was the helmsman/navigator of RPs and not the cook. Nami is the navigator of SHPs.
If Gaban has CoC/ACoC then damn RPs were stacked. Prime RPs who reached LT had 4 ACoC users (Roger, Ray, Oden and Gaban), they could make their own WG at this rate. I hope we get some God Valley flashback to see what really went down.