Graphviz dot support is weak.
If lossless read then write is a goal, a complete dot format representation will be needed. In addition, a mapping of dot format elements to graph package elements.
Consider adding direct support for all graph types. Consider (re)adding support to generate diagrams in tutorials. (Example, graph attributes for rankdir in adjacency list tutorial.)
Edit: These considerations done. All graph types supported, example diagrams generated.
Next feature needed for tutorials is something to highlight a path. Maybe this could be added with some hardcoded appearance without stepping into full attributes, maybe just wide lines. Maybe highlight a FromList?