Nintendo of Japan is poorly-equipped to handle the DKC franchise as a whole, let alone its individual characters. One logical explanation for this that came up on the latest Kongversation was that gorillas never really became prominent in Japanese pop culture, therefore, whenever they handle DK, they characterize him as this over-the-top deranged grinning "stupid ape" because they really don't know better. Contrast this with the West, where gorillas have generally been known as peaceful, powerful creatures, and you can see where the divide comes from.
Retro would absolutely handle K. Rool's character in a positive way; they took Cranky and made him actually cranky again, instead of just a generic old, wise man, so it's clear that they're aware of how the characters should actually behave. The meme on places like NeoGAF is that "anyone can handle the DKC franchise [therefore Retro should make games that aren't DK instead]," but, comparing Jungle Beat to Returns or Tropical Freeze, and how each was received, that's clearly false.