The appearances of Cosmic Armor Superman in comics can be a bit sporadic. You could come across him in specific DC comic runs or special editions. It's best to check with comic book stores or online comic databases for exact details.
In comic vine, it's a tough call. Superman is incredibly powerful, but Batman is known for his intelligence and preparedness. It could go either way depending on the circumstances and the writer's imagination.
There could be a wide range of characters in the 'cosmic watch story'. It might have a young protagonist, perhaps a curious child who stumbles upon the cosmic watch. There could also be an old wise figure, like a mentor who knows some of the secrets of the watch. And of course, there might be antagonists, like a group of thieves who want to steal the powerful cosmic watch for their own evil purposes.
The Spartan Rage Armor is a great choice. It gives Kratos a significant boost in strength when his Spartan Rage is activated, which can be very useful in tough story battles. It helps in dealing more damage during those intense moments when you need to overpower enemies quickly.
I'm not sure specifically as I haven't read it. But they could be astronauts, space explorers, or even beings from other planets. Maybe there's a brave captain leading a crew on a journey through the cosmic sky.