Allow for simplified node and font sizes (XS, S, M, L, XL)

[jsoconno]

Is your feature request related to a problem? Please describe.
No.

Describe the solution you'd like
As an end user or architectures, you may not want to think too hard about what attributes are used to adjust certain settings. In particular the size of nodes or fonts in a diagram. We should look into the feasibility or benefits of a simplified input of something like XS, S, M, L, and XL while still giving the user the ability to more granularly update these attributes.

Describe alternatives you've considered
None.

Additional context
None.