I'm not convinced Goku can breathe in space. That's only something Frieza can do. In RoF Frieza took out the Earth and Vegeta died, even though he likely could have tanked the explosion. What they seem to do is just hold their breath for longer than the average mortal.
What ifs can set parameters like morals on and bloodlusted. One where characters won't do anything they usually would do, the other where they would win at any cost. If you go with the "every what if is no holding back" then every discussion will end in Dragon Ball character going for BFR unless it's a character who can fly/survive in space. This is not really an accurate discerning of who's more powerful. I'd like to say for the sake of arguments it's morals on, so unless it's the *only* way of beating the opposition, I don't feel characters would go for that last resort.
Anyways, Kratos was able to hold open Kronos' fist, with Kronos being a 1600ft giant with a clap force over billion Newtons, which would equate to at least 125,000 tonnes lifting strength. Not to mention he pushed back Atlas, who holds up the sky, which has no defined limit on how much that weighs. In terms of durability, Kratos is unscathed by Zeus's lightning bolt which casually shatters mountains.