>Doom has insane chemistry with Stark, Strange and Namor
>instead of being the rival of Stark or Strange, or even the Panther, he's instead the rival of the most boring superheroes on the planet, the Fagtastic Four
The swap ala Kingpin should've happened ages ago. Doom V. Reed simply doesn't work. They have never, in their entire history, had an interaction with a modicum of pathos. It's just Doom attacking the Four Fags, Reed figuring out his plan, being cold but also trying to appeal to his "better nature", Doom screeching autistically, and it ends after Reed invents a doohikey to blow him up with no emotion. But then you read stories where Doom fights Stark and Strange and there is genuine chemistry between them, whether they're frenemies of full blown rivals. Same with Namor. These guys have tussled more times than they've teamed up and they're still full-time allies.
>inb4 Reed is just the one guy to get under Doom's skin
I'd get it if it wasn't so boring. Reed is boring. That's his thing. He's an analytical explorer. I get it. The FF are boring. They're not for me. Fine. But when you have this ultra bombastic character getting triggered by the human equivalent of stale bread, then there's no reason for me to be invested in it. At some point Doom would've just shot Reed and the FF with a magical sniper rifle and that'd had been it.
Beyond that the genre clash just makes no sense for them to be rivals. Luthor and Superman work, they're both Sci-Fi characters. Joker and Batman are both noir horror. Doom is a literal wizard in a castle fighting a guy in a jumpsuit. Stark has the core of the armoured egotistical flashy supergenius who cannot into magic, and Strange is the reverse of that. Pitting Doom against them works, especially as Stark Post-Extremis should be infinitely smarter, the rivalry being normal intelligence vs enhanced humanity. And Strange is the SS, that's a far bigger position for Doom to covet. Even Panther works better as a main rival.