I kinda get what you mean. Personally, I'm not a huge fan of King Rad. I mean - let me clarify - he's a great character and I've enjoyed his role in this story.
But I think this strip (http://drmcninja.com/archives/comic/25p107/
) demonstrates it best. King Rad is the foil for the good Doctor. Because both are quite radical, but the Doctor is devoted to preserving the ordinary as well. The Doc is not okay with people dying just to make the world more cool. He likes healing people. He likes his Honda Accord. He walks dogs. He treats diabetes. His parents dislike him because they're off doing rad ninja things and he insists on helping those ordinary non-radical folks do ordinary things like living and not being cool.
The Doc has always been about this tension between the Doctor - the regular guy who wants to help the greater good, the huddled masses - and the Ninja - the radical guy who kills those folk without a thought. And McNinja has to struggle to reconcile those two aspects.
But the King - the King doesn't have that struggle. The King is also inherently full of so much awesome and radicalness, just like the Doc. But unlike the Doc, the King doesn't give two craps about the ordinary. He's got a special little elitist hierarchy based on coolness, and he doesn't care about those huddled masses and making their lives better - they're just not cool enough to care about.
In the end, that's the divide. Two inherently radical characters, but the King just doesn't really care about people, whereas the Doc takes on the responsibility to care - and all the burden that it brings. That's why the Doc doesn't like the King. (Or maybe it's why I
don't like the King, but hey, it's my interpretation and I'm sticking with it).
But, for me as a reader, this conflict extends beyond just the realm of the story. Because I also think King Rad is also representative of what the comic (the Adventures of Dr. McNinja) could easily devolve into - meaningless nonsense in the name of lulzz and teh randomz. (Entirely personal opinion - just me talking here)
See, absurdist humor is a very fine balance. We live in the internet age and random nonsequitur humor is all the rage. And nowadays, it's easy to make something absurd and have it called "AWSUM." Raptor Panda Squadron. Dragon Riding Commandos. Zombie Motorcycle Gang. Kung Fu Dracula. Samurai TIme Travelers. Robot Seals in Space. Laser Explosion Penis. Bikini Wizards. Cyberspace Rockstars. Steampunk Street Fighters Dancing On Trampolines Who are Also Ghost Cats That Are Secret Agents.
Those are just off the top of my head - but I guarantee someone on the internet has already published them. They're examples of what happens when the drive towards "radical" ends up losing any sense of subtlety. They just run off the rails and drop straight into "silly," then "dumb." Hastings actually kind of parodies that in this April Fools strip (http://drmcninja.com/archives/comic/11p9/
- "how crazzzzyyyyyyy")
Absurdity necessitates reality, in order to be absurd - otherwise, it's just pointless and ungrounded.
Dr. McNinja is pretty absurdist - but the genius is that Dr. Hastings is really good at keeping it grounded enough to make the absurd work. I don't get tired of a doctor who is also a ninja because the world he exists in still makes sense. The Doc is not always pulling some nonsequitur out of his ass to get out of trouble. ("Hmm, this looks like a job for my Psychic Shark Posse!") But King Rad? King Rad kinda is.
Rad is absurdity without limits - he's literally from the "Radical Dimension" where they have lost all sense of subtlety and just devolved into nonsensically "aww-sumzzz." Basically, the Radical Dimension is the Internet. And King Rad wants to remake the world into that image.
So this conflict between the Doc and the King isn't just a plot conflict to me. It's a battle for the very soul of the comic. Either it stays as the Doc McNinja we know - pretty insane, but just grounded enough that the insanity is funny not stupid - or it becomes every webcomic involving TEH R4NDUMZZZ that you see floating around the web, often involving Megaman characters.
"Megaman Fights Leprechaun Godzilla In a Volcano" - probably somewhere out there.