I'm not saying rush through character development. I'm saying rush through the stuff that isn't character development, that isn't important to enjoying a classic Fantastic Four adventure.

I'm saying skip the expository stuff. We don't need it, and there's so much better stuff that it gets in the way of. We don't need to see them go up in a rocket for the movie to communicate Reed's guilt and Ben's struggle. We don't need to see them get bombarded by cosmic rays to understand that they got their powers in space.

Their character development happened over the course of 60 years after the accident, not just within those first couple months we don't see in Fantastic Four #1. The "definitive versions" of these characters are complex arcs encompassing 60 years, not just the stage they're at in comics today (see: Dan Slott's Reed in DS2). Put another way, most MCU leads have consistently reflected the "definitive versions" of their comic selves, despite complex character arcs and drastic changes.

So pick up with them after the accident, and then follow them on a fantastic adventure. That's the appeal of the title. That's what a Fantastic Four movie should sell. That's how we dive right into the real characters and their real arcs. Everything else is exposition and prequel-itis.

(This is one place (of many) that the 2005 and 2007 movies tripped up - they put all their focus on the expository stuff - the accident, Reed and Sue pre-marriage, how they got the Baxter Building and Fantasticar. They spent their runtimes inching towards status-quo, and never actually got around to what makes a Fantastic Four story a Fantastic Four story.)