The Fantastic Four are the crown jewels on the Marvel comic universe. Even when they were not the top selling comic, the characters and their villains have been central to what happens in most of Marvel Comics.
Yet the Fantastic Four movies have been disappointments in terms of box office and critical success.
You have to go back to the 2012 Ghost Rider Spirit of Vengeance for a Marvel related movie that had a lower first weekend box office performance than the most recent Fantastic Four movie.
My analysis will have spoilers for the Fantastic Four in comics and for the Doctor Who TV Show.
The characters of a live action science fiction-fantasy that most closely approximate Reed Richards (Mr Fantastic) and Victor Von Doom (Dr Doom) are Dr Who and his arch enemy the Master.
Reed Richards can go to any dimension and anywhere in time and space.
Reed Richards made a portal to the Negative Zone.
He made a bridge through which he can look at other universes in the Multiverse and where he could travel to them as well.
Reed creates custom versions of TARDIS capability as he needs it.
He made devices where he could shrink into the smaller dimension Universes (Microverse)
Dr Doom can as well.
Dr Doom made a time traveling platform.
Reed Richards and Dr Doom have a chance to defeat ANY opponent no matter how powerful. This does not mean that they WILL defeat any opponent but they might.
Reed Richards with the Fantastic Four defeated Galactus multiple times.
Dr Doom stole the Silver Surfers powers, and the first Beyonders powers and then killed and took the powers of the rest of the Beyonders.
They are like Dr Who and the Master in that they have supreme alien level intelligence and get find the secrets of the Universe.
Dr Who can defeat the Master but the Master can defeat most anything else in the Universe. There are things in the Universe with more raw power than either of them. However, through intelligence, devices and plans they can often overcome most any challenge. Their limitations and failures are part of the stories. However, a core assumption is that they can probably come up with something that can win and exposition is for telling us what is limiting or preventing them from doing it. Exposition is not to justify why they can do something. By default it is believed by the viewer that they can do it.
The movies make a fundamental mistake in diminishing Dr Doom by not having him be a big part of the creation his own armor. They also should allow him to have his magic and his super-science.
The creation of the armor, forcefield and other gear are only minor first miracles before things really get rolling.
Richards has the rest of his team who are his family. Just as Dr Who has companions. However, Reed Richards has consistent companions who have powers and are family.
In the original story Reed Richards and Ben Grimm were veterans of WW2. Ben Grimm was a pilot and Richards worked in Intelligence. They were college roommates and best friends.
However, story wise they basically as close as brothers.
Just as Alfred is not actually the father of Bruce Wayne (Batman) by blood or legally but Alfred really is as a father to Bruce Wayne.
Dr Doom and Richards also went to college together.
Doom attempted to go or contact the Underworld to free the spirit of his dead mother. His mother was a gypsy who used magic.
Doom is an orphan and is attempting to restore aspects of his family.
Richards tried to help Doom with Dooms attempt to make a device to go to the Underworld. However, Doom was too arrogant to accept the help.
Dr Who and the Master were both from the same home planet. They are often and usually apart from the others of their race and planet.
Dr Who can regenerate and has two hearts and has other physical differences and what could be considered powers. They are secondary to his intelligence and what he knows and what he can create. This is the same for Reed Richards. The powers and the appearance are secondary to the intelligence, what he knows and what he can create.
The television Dr Who had horrible special effects most of the many decades it has been on the BBC.
The shows still worked because you tell and show as best you can what the viewer needs to understand and believe within 2-5% of the running time and then you are off the solving and having a rip-roaring adventure across time and space.
Reed Richards can make mistakes. The FF got their powers when he made mistakes about shielding his rocket.
The FF are adventurers and explorers. They explore and find problems. They may create problems.
The team and Richards try to solve the problems.
This is unlike the Avengers who are super team for protecting and saving the world.
Another team with some similar dynamic from live action is Stargate SG1
Stargate SG1 had Samantha Carter who could figure out most any technical device.
Dr Jackson could figure out any universal secret.
Reed Richards would perform the Carter and Jackson role although occasionally some technical solution or universal secret insight can come from Sue Storm or one of the others.
Dr Doom would be like the character Baal.
The roles work at different power levels.
Like Batman Begins and the Dark Knight, there should be separate movies for introducing the heroes and the main villain
In terms of time available in a movie, it is too much to have the hero origin and the main villain.