I'm not sure who the absolute best is, but there are some well - known names in the fanfiction community. Some authors who have a good reputation for writing about superheroes in general might also write great Spider - Man and Lizard stories. You can check out fanfiction platforms and look for those with high ratings and lots of reviews for their Spider - Man and Lizard works.
One possible villain could be Doctor Octopus. He might be back with some new and improved mechanical arms, and he wants to prove that he's the superior scientist and villain by defeating both Spider Man and Spider Girl.
The Green Goblin is a main one. He's always causing trouble for Spider - Man. Norman Osborn, as the Green Goblin, has a complex relationship with Peter Parker, which makes their battles even more interesting.
The main villains in the Cosmic Spider - Man story are quite interesting. Firstly, there's Mysterio. In this story, he uses his illusions in a more cosmic - level way to deceive Spider - Man. He teams up with some other villains to try and bring down Spider - Man. Then there's Sandman, who has been corrupted by a cosmic force and is now a more menacing foe. Another big villain is Carnage. He has a new form that is powered by a dark cosmic energy. All of these villains pose different threats to Spider - Man and his new cosmic - powered self.
Some of the main villains in Insomniac Spider - Man 2 are Kraven the Hunter and Venom. Kraven is a formidable foe known for his hunting skills, and Venom brings his own unique set of challenges with his symbiotic powers.
Green Goblin is very memorable. His crazy laugh and the flying glider make him stand out. He has a complex relationship with Spider Man as Norman Osborn is also connected to Peter's personal life.
One plot idea could be that the Lizard is actually being controlled by an evil scientist who wants to use him to take over the city. Spider - Man has to figure out how to break the control and save his enemy. Another could be a story where the Lizard has a moment of self - awareness and teams up with Spider - Man to stop a greater threat. For example, a group of aliens that are attacking the city and both of them realize they need to work together.
Perhaps the Lizard's story in Spider - Man 5 will explore his origin more deeply. It could show how he became the Lizard in the first place and what his true motives are beyond just causing chaos. Also, Spider - Man might have to develop new strategies to defeat him as the Lizard could be smarter and stronger than before.