King Dedede is the only canonical villian I can think of that is canonically not evil.
In fact, King Dedede is one of the most interesting villians I have ever met because he maintains his personality both as an ally and as a villian.
Does that remind you of anyone?
Lex Luthor, Magneto, Doctor Doom. All of them have allied themselves with forces of good or done benevolent things at times. Magneto was a good friend of Professor X and has joined, left, and even led the X-Men at times. Lex Luthor became president of the United States and his technology has aided the DC heroes on numerous occasions in some way or another. Doctor Doom has also aided Marvel heroes in times of crisis out of a sense of both honor and vanity - he refuses to let anyone besides himself rule the world. He is also treats the people of Latveria like his children, and in an alternate future he becomes the US president and solves a multitude of problems with the dystopian future, namely the near-elimination of crime.
Likewise, King Dedede and his subordinate, Metaknight, have joined forces with Kirby several times, putting aside their petty differences over who stole how much food from where and fighting the real enemies like Dark Matter and Nightmare. In a more heroic non-canon example, (another thing he has in common with the 3 comic book villains - he's more heroic outside of the main series canon) remember what Sakurai said about his role in the Subspace Emissary: Dedede was presumably offered an alliance with Tabuu but refused, knowing that it would only lead to needless destruction, and instead created a mechanism to combat Tabuu's most powerful attack, the Off Waves, and even selflessly sacrificed his own copy of this pendant in favor of giving it to Princess Peach/Zelda.
Also, all characters are unique in that they have such capacity for good, but instead choose other paths for their personal gain. They all have more than enough power and influence to change the world for the better, yet for their own reasons they choose not to - Doom out of hate, Magneto out of spite, Luthor out of greed, and Dedede out of selfishness. They are so unique in their worlds as many other villains have no capacity for good due to irrational spite (Lady Deathstrike), apathy (I can't think of a good exaple for this), or just being bat**** crazy (The Joker).
Dedede is indeed a complex and formidable character.
We should talk more about this in the Kirby thread.
