Nice--as the above poster notes, linking statutes and their interpreting rules and regs. in a sensible way could be a nice differentiator. E.g. if a regulation or another code section gives a special definition for a term used in the statute, it shouldn't be too hard to generate a default annotation linking to that definition, especially if you're already doing this for inline citations in cases.

Definitions are not as uniform as citations, but they are still pretty formulaic. "_________ shall mean ________" etc.