Though Kingpin has super-strength in the comics, that's not his real superpower.

His power is Batman-level planning skills and Dr. Doom level ruthlesness. He would destroy Peter Parker's entire world and make him watch it while it happens.

He would out his secret identity. He would buy the Daily Bugle and give Jameson unlimited funds to destroy his image. He would arrange events so that Peter seemed responsible for someone's death. He would make Stark & all the Avengers hate him. He would make him the most hated person in the city. He would seduce Martha and make her his side-piece. He would ruin Peter's career aspirations in any scientific field by buying his employer's company. He would buy scientists to publish scientific papers refuting Peter's research.

He would laugh as he did so and make Peter watch every excruciating moment of this with the full knowledge that neither he nor Spiderman could do anything to stop it.