Assuming the API supports it, the ability to customise the graph nodes’ colours and text would make it easier to separate what cards (markdown files) are used for what. For example, we may have front-matter indicating that the card relates to a person, and another to a concept/definition, another to Map of Concepts (MOC) etc. We could prefix each category by an icon, and change the node colour. Like the example below:
This could be realised by mapping a front-matter parameter (category) to a set of colours and optionally icons, or alternatively mapping to tags.
My #1 use case for this is to color code based on a ‘state’ or ‘status’ attribute in the front matter. For example, I draft blog posts in Obsidian and I have a work flow that includes states such as idea, outline, draft, published. It would be nice to see the published ones displayed in a darker shade of color than those in the other states (or even different shades for each state).