There's never going to be a system that is fair to everyone
Floor exercise, the longest you run is two or three steps. In the vault, it's not a whole lot more than that.
I was always athletic and I could do a lot of things
In gymnastics, you have to be perfect every step along the way.
If you can't handle all the injuries and scars, choose a less demanding sport.
Gymnastics is the type of sport where you can't take something that gives you more energy. Something may be great for the vault, but then you have the bars after it and you have to be more sedate for that.