On the hypothetical that he looks to try the idea again, if Dixie is essentially made as a Falco to Diddy, it would theoretically be less work than if Dixie was 100% unique (which, let's face it, isn't going to happen either way). What was so problematic about the duo before couldn't be more complicated than Rosalina to be frank.
And yes, I am well aware that either way, Dixie would take time to make (a point I brought up in the last page), however, if Dixie is added to Diddy rather than made separate, Sakurai's mindset could be that he merely "completed" what he had planned from the start and see K. Rool as a "real" new challenge.
Not saying it's going to be the case, that it's likely, or even that I want to see it happen, but its honestly not that farfetched. Hell, if it were up to me, I'd just add K. Rool and Cranky while throwing in Dixie as a Wolf Diddy only if there was enough time.