Add size option to each button individually

I have buttons without labels only icons. I am using it on a Tablet and I need to make the buttons bigger so I am inserting spaces in the label. But the icons are not vertically centered on the button. If you will be able to add an option for each button to have a preconfigured size (in pixels) then I can deselect the label options for buttons that I want them to have an icon and set the size instead.
I acknowledge that it is not a functional problem and only a minor aesthetic issue but it would be nice if you can add this option.

Thank you