Diagram visuals

[RNSS]

• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the issue tracker for a feature request that matches the one I want to file, without success.

Is your feature request related to a problem? Please describe.

• The text is very close to borders
• Ability to change default font
• Ability to change default shape borders thickness

Describe the solution you'd like

• Add more space in all directions
• Ability to change default font
• Ability to change default shape borders thickness

Describe alternatives you've considered

Additional context

[davidjgraph]

This is too vague and contains multiple issues. I can convert this is to a discussion, but it's zero use to anyone in it's current form.