If you want to toss blame around and point fingers at anyone for the quality of Fant4stic -- look no further to 2 writers who came up with the Ultimate Fantastic Four -- Brian Michael Bendis and Mark Millar.
They turned the founding family of the Marvel Universe into kids working under Franklin Storm. They facilitated the debacle that ended up in this movie.
Some scenes, lifted from the comics themselves, were executed perfectly, but 2 scenes - a garage scene with young Reed and Ben, and Johnny's flame on moment under observation after the accident -- are just not nearly enough to build a movie on.
What I see is an ego trip from Millar, Bendis, Trank and Kinberg that led to something of a Trank-Kin-stein's monster of a movie. Millar and Bendis trying to make the Fantastic Four "new and fresh" and Trank and Kinberg trying to put their own spin on that "freshness".