Honestly, there's only one thing I hate about this story that's so OOC for Doom everything else is about in character for him. The only truly OOC think is him making a deal with demons for more power.
Doom is a man who takes power never make's a deal for it unless he must ala Iron Man: Legacy of Doom (he needed the shard of Excalibur Mephisto possessed that he got from Morgan Le Fey and the only way to do that is to deal Iron Man to Mephisto). No harm or foul to Doom. Here there's obviously a price Doom will pay for this deal. In fact it's his downfall in this story.
Time and time again we've seen Doom do what most men in his possession do.. crave more power. But it's the fact that Doom take's it for himself than make bargain level deals for it. And to me that's the big flaw in this story.
There was no real need for Doom to do what he did to Valeria. Nor make the demon deal for a power increase. At this time it's well known Doom is second human only to Stephen Strange himself when it come's to the magic arts. But his power should already be up there. The dude's learned from the best magicians in the world (Morgan and the dude from Iron Man #149 being the best examples). And as we learned in the 90s Thor Annual if there's a sorcerer as powerful as he? He'll go out of his way to grab that power for himself which HE HAS. The fact is Doom already has the power. It's just the fact writers seem to think nah he has to crave more and think it's not enough. Then if it's not enough how come he has unlimited ammount of robots, yet he always seems to be lacking in magical creatures when it's known he's the best of both?
Still, the moment with him just rubbing it into Reed over try and learn magic is classic Doom. The man would absolutely rub it in his great enemies face that he has great knowledge of something the other does not.