I think, in general, what people mean when they use the phrase "spiritual successor" is that it would be a tense boat ride featuring menacing encounters with a monster. Beyond that, I'm not sure that anybody would necessarily be expecting skippers, which is the one touch that really would tie the attraction back to Jaws (and Jungle Cruise, going even further back).
I'd like to see a mostly-indoor boat ride down a jungle river at nighttime (sort of a toned-down, real-world, darker version of Na'vi River Journey in terms of the environmental aesthetics, but on a larger scale), with creepy scenes akin to the tone of the boathouse from the Jaws ride.