They divided the groups into Super-Heavyweights, Heavyweights, Super- Mediumweights, Mediumweights and the ones without super strength.
Actually, Spidey didn't have a problem with his class, the Super- Mediumweights; it was a nice bunch at that time: Valkyrie, She-Hulk, Colossus, Ghost Rider, and more. He even said:This is my strength class, folks. A nice bunch, really. Of course none of them have my amazing speed, agility or other spider-like powers...
Captain, along with Daredevil, Wolverine, Iron Fist, etc. were in the lowest class, without super strength.
I guress you can still find it in here: https://comicvine.gamespot.com/profi...-heroes/20380/