^I think it makes for good TV, it's just too expensive.
It's pretty straightforward for me: if you like Coulson, you'll like SHIELD, as it's Coulson's show. Coulson has no powers, he is a completely original character who deals with superpowered shenanigans, including artifacts and potential superheroes, without actually being a superhero, or even a sidekick, and not directly confronting people who are trying to take over the world... well... except that one time, and that... didn't end well.
The fact that he is backed up by a team of original characters only testifies we'll be getting more of the same from Coulson as opposed to a superhero-ized Coulson.
I think part of the premise of dealing with a world of superheroes is the fallout, y'know? All these weapons from the alien ship. People trapped in rubble from Hulk's rampages, or some crazy dude's experiments with stored Cosmic Cube energy. If you treat the MCU films like, I dunno, a previous Star Trek series, there's at *least* season's worth of stuff to build off of, and there'll be more as Phase II goes on. And there's enough coherence there to build things into that Universe that aren't really the films either people experimenting with Darkforce or a Inhumans plotline... all sorts of cool stuff.