If you want to resize a variable and have it stay resized next time you run a program you would have to do the resize in code, or if it is loading the variable from e.g. a .mat file then do the resize and save the updated variable to the mat file before re-running the program.
Preferences -> Command Window -> Format.
Preferences -> Variables -> Format.
control the default formatting of numbers in, respectively, the command window and variable editor. (Note, that is from Preferences in the Matlab Home ribbon, not in code, I just used a code block to split the two instructions for readability). You can change it in the variable editor on a one-time basis from the ribbon at the top.
I don't know about how you can influence the style of number format on axes though.
