I don't know about size cause I thought about it and tried different sizes and I wonder if the gravity was not also dependant of the size. And movers will take CPU and thermos ressources. I think from memory the maximum gravity settings was maybe 400%. They should allow at least 1000% seeing that some Mario games have even 1100% gravity settings.
I'd be surprised if gravity depended on size - otherwise small items would fall at a different speed to big items. While it would be ideal to have higher gravity limits, I wouldn't be surprised if they'd set that upper limit based on what their physics system can cope with, generally, and still remain stable/robust.
Size certainly ought to work assuming there isn't anything bizarre going on with the gravity. Objects fall at the same speed regardless of their size/mass. If you halve the size of everything in your world, things will
appear to fall faster because they have fallen further relative to their size.
Talking about the physics of Mario is a bit dubious because you start with an assumption about his height. If Mario is human sized, then his gravity is very high. If Mario is ant sized, then it isn't.
