(Tangent: It's one reason I thought Warehouse 13 was brilliant in concept, because the people mostly stayed people, and it's the objects that wandered around and did strange (and usually dangerous) stuff. )
The original was the "Friday the 13th" show. http://en.wikipedia....the_13th:_The_Series
Warehouse 13 just rehashed the same thing. (Most good stories do that.)
The people concepts tend to be pretty simple.
Where would you classify characters like the modern Batman and Iron Man? Wayne and Stark are both normal humans. Perhaps a lot more technologically sophisticated and wealthy than most people. But their 'super' powers derive mainly from the technology and powered bodysuits they employ. If they have any super power it's their high IQs.
Or Doc Savage? His powers derive mainly from a physical and mental developmental training program that started when he was conceived. No super anything with Doc. The implication is he's just a more 'realized' human potential. And that what he is, you could be too.
Where do these characters fit into the general superhero continuum?
Check the GURPS or Palladium or Heroes RPG systems. They work very well.
Many other systems also have the same situation.
I think I'd like a polar bear with shape shifting, mimic, transferal possession, and a specialization in snake style kung-fu. Oh, and for psionics, we'll go with mind trap and bio-manipulation.
In the Palladium world... that's just friggin' SICK!
A TMNT martial artist with super-powers? Yeah... move over...
Sigh... haven't played in many years now, but I sure as heck know how to game the system and make the most disgustingly powerful characters you've ever seen.
But just think of these characters in terms of some gaming systems or worlds. Call of Cthulhu
There are 3 systems where it doesn't matter what your character is:
1) Call of Cthulhu - they all go mad & die
2) Paranoia - they all die
3) kill puppies for satan - uh, yeah... they die too
Movies are little different. With numbering from above:
1) All horror movies
2) All sci-fi horror movies
3) All comedy horror movies