For those of you who didn't follow Fant4stic closely, I'll give you one (of hundreds) examples of why I believe Simon Kinberg is absolutely terrible.
Ben Grimm / The Thing is my favorite Marvel character of all time.  Here's an excerpt from Marvel Wiki detailing some of Ben's backstory:
Benjamin J. Grimm was born on Yancy Street on Manhattan's Lower East Side, where he grew up in poverty. His father, an alcoholic, was unable to hold a job. Much of the family's income came from Grimm's older brother, Daniel, who obtained funds illegally as leader of the Yancy Street Gang. Grimm, who idolized his brother, became embittered against the world when Daniel was killed in a battle between rival gangs. Grimm was only eight years old at the time. Within ten years, he had succeeded his brother as leader of the Yancy Street Gang. After his parents died, Grimm was taken in by his Uncle Jake, who had risen from poverty to become a successful physician. At first, Grimm resisted his new guardians' kindness toward him. But eventually, he came to return their love. He left his life with the Yancy Street Gang behind, entered high school, and became a football star there. While he was a senior at Stuyvesant High School, Ben received a football scholarship to State University in Hegeman, New York.[6] On the football field, Ben received the nickname "Grimm Reaper."
http://marvel.wikia.com/wiki/Benjamin_Grimm_(Earth-616)
Of course anyone who saw the movie knows that everything about Ben's background and character were crumpled up and thrown out the window.  Instead of being from the Lower East Side, he was from Long Island.  Instead of being caught up with gangs and idolizing his older brother who ended up dead as a result of gang activity, he was abused by his older brother (who was a mindless jerk).  Instead of being a burly football player, he was a small guy who didn't have the size to play football.  Instead of dealing with his problems with a self-effacing sense of humor, he had no personality.  Instead of having a heart-of-gold beneath a gruff exterior, he used his super-strength to mercilessly kill people for the government etc. etc. etc.
All that is bad enough and inexcusable, but the worst part was Kinberg's smug explanation of why he made these changes and how he thought his character was "more interesting" than the iconic character that fans have loved for over 50 years.
The change of Jamie as Ben being a smaller guy instead of a bigger guy, for example, was for a purpose," he said. "It's more dramatic when that character becomes a huge rock creature  that's a bigger transformation. The notion of a working-class tough guy who's been pushed around by his bigger brothers his whole life seemed like a more interesting character than the guy who started as a football player and just ended up being 4 inches taller.
http://www.latimes.com/entertainmen...fantastic-four-casting-controversy-story.html
It remains to be seen how he'll make the X-Men "more interesting" but it's frightening to think about where his tiny mind could take us.
Professor X is secretly a serial killer?  Jean Grey's parents were really mole people from the Earth's crust?  Storm is a Kardashian?