How would the novel's flavor be different if Pi's sole surviving animal had been the Zebra or Orange Juice in Life of Pi?

In the final chapter of Life of Pi, having come to the end of his fantastic, harrowing journey, Pi presents the possibility to the rapt interviewer that his entire story is an allegorical account of desolate death and forced cannibalism among humans, not animals. Pi explains that Orange Juice, the orangutan, is actually his mother. The zebra represents a poor sailor, and the hyena represents the unkind chef. Pi, himself, is Richard Parker—the Bengal Tiger. When Pi suggests this alternate version of events, he invites the interviewer to consider which story is better: fully acknowledging that "better" is a heavily-loaded, subjective term.
This is an important part of the novel to remember when wondering how the flavor of the story would change if Orange Juice or the Zebra survived instead of Richard Parker. Presumably, if this were to happen, the protagonist of the novel would either not survive the story or the protagonist of the story would have to shift. Either of these changes would profoundly impact the scope and direction that the novel takes. Perhaps it would be a story about a mother's grief or a sailor's second chance, but it almost certainly could not be a story about the life of Pi.