Honestly of the Rare games, only DKC 1 and 2 had a cohesive art direction, 3 was so-so, enemies designs were way more silly, the Bear Brothers and Banana Birds felt that they were trying a "children's adventure" aproach to that title but still worked most of the time, meanwhile on DK 64 we were struck with stuff like this:



Most of the stuff that worked were characters directly imported from the first 2 games and new additions for the DK crew, everything else was all over the place.
Now on the gameplay department, the game is clearly more a spiritual sucessor to the Banjo games than a sequel to DK 64, is funny seeing people complaining about the straight-forward approach of Bananza when they spent years complaining about how 64 was convoluted with multiple gameplay styles. Reminds me when people started complaining about how 3D Mario got streamlined and when Odyssey released people came out of nowhere to claim 3D World wasn't that bad and deserved a second chance.