Spectacular is a totally original character and not based on anyone at all.
Well, okay. The truth is I wanted a science teacher, but I didn't want to use my Iron Man spin-off, Warmonger, because I wanted to have a gadget class separate from science class, which my Batman spin-off would have taught if not for the fact I wanted him for my Combat Ed. class. A Mr. Fantastic spin-off was the obvious solution.
I've never been much of a fan of the Fantastic Four. I appreciate what they were when they emerged onto the comics scene (in my opinion they were the first great super-team; rather than a collection of established heroes, they came out on their own, together). But now, like just about every character DC has, they just feel too dated to me. I feel like it does some characters a real injustice to continue to use them and constantly reinvent them.
I can remember reading things with Mr. Fantastic from back in the day where he angrily lashed out at Sue Storm for interrupting his work, and so I wanted my version to be like that all the time. To Spectacular, nothing's more important than whatever it is he is working on at the moment, damn everyone else and sucks to the consequences. He's the smartest guy around and he knows it, so he acts like it. It's hard to imagine someone being humble and wholesome who's as smart as that. If anything, they'd at the very least find it difficult to relate to others in a social setting. Spectacular (which sometimes, in my head, I pronounce as Spectacu-lahr) takes that to the next level. He doesn't bother trying to relate with others, because they're just not as spectacular as he is, anyway.