Implementing Hit Location, Critical, Reaction tables directly into the ruleset or by means of an extension.
If they can be open to customization for adding more entries (for instance, the expanded reaction tables in GURPS Social Engineering), that would be awesome too.
Right now, even at least one Roll20 GURPS character sheet is automating hit location and even damage by type (cutting, piercing, etc.).
Automating damage by location can be interesting as well.
Cheers