As you know figures in a journal paper must have a specific width (e.g. column width or full paper width), however, adjusting the figure size after plotting it changes the resolution and makes the font sizes non-uniform and often inappropriate (appear too big or small). So when I have to specify the width manually before plotting I encounter two issues: the margins and the aspect ratio. I want to make maximum use of the space so I want to have a tight bounding box. In both Matlab and Python this task is a real headache, and leads to either changing the aspect ratio or the initial size of the figure. Do you (personally) crop the white spaces or leave them to be? And do you use the default aspect ratio? If no, how do you set it?
Edit: I am NOT new to these software and my question is not about technical details. I am just curious to know what general approaches people take.