For Spider-Man villains, the big guns are the Punisher and the Jackal. Small timers I like are Cyclone, Hammerhead and Carrion. I love Cyclone and his goons with their Marvel Franglais. He’s a ridiculous villain but his stories reprinted in Marvel Tales and his Spectacular Spider-Man story with Moon Knight hit me at the right time. Hammerhead ‘s origin wouldn’t work today but I love when his love of old gangster movies pops up. Carrion’s story was my 2nd Spider-Man mystery after the Wraith but the Carrion story carried more weight.
In the Fantastic Four, I like Darkoth. He had a great look and his connection to Dr. Doom made his story more important. Evil Reed/the Brute was a real interesting villain. I don’t know how great the Air-Walker was but I know I was excited when I got those first issues as back issues. Loved the covers.
I like the Headmen from Defenders though I believe they first appeared individually before the Bronze Age. They’re creepy. I love Nova’s villains: Sphinx, Condor, Diamondhead and Powerhouse. I’m one of the few who liked Vermin in Captain America. The Orb creeped me out as a kid. I had the reprint of his Marvel Team-Up story in the Astonishing Spider-Man Treasury Edition.