I think it would work better if they showed a series of flashbacks of how Reed and Doom were something like "Friendly rivals" from Reed's POV whereas Doom saw him as an insufferable genius type who pointed out every single flaw in Doom's experiments and theories. Finally Victor got so fed up when he saw the spaceship Reed was designing (because of how great it was) he proceeded with one of his more ambitious experiments even though Reed again pointed out the flaws, and then we get the explosion.
Thus, this sort of gives us some sympathy for Doom since Reed was an unintentional jerk to him for always pointing out his mistakes and the like (Doom's colossal Ego considering this as blasphemy) and "driving" him to the experiment that destroyed his face.
Then cut forward and Reed finds out Doom became King of Latveria, and has been spying on Reed for years. Now that he sees how Reed is Mr Fantastic he wants revenge (because now Reed is world famous, moreso than Doom).
Thus, this sort of gives us some sympathy for Doom since Reed was an unintentional jerk to him for always pointing out his mistakes and the like (Doom's colossal Ego considering this as blasphemy) and "driving" him to the experiment that destroyed his face.
Then cut forward and Reed finds out Doom became King of Latveria, and has been spying on Reed for years. Now that he sees how Reed is Mr Fantastic he wants revenge (because now Reed is world famous, moreso than Doom).