1) Space Vehicle Suppliment
2) Ground V supp
Note: maybe a product like SM2's Armored Assault an Starstrike
3) Setting background book or books; advanced racial makup info, campaign plots, (political, social, economic, racial, trading, crime, etc) factions, more indepth world info, trading routs etc. [I have not had a chance to go back and read the HARP SCI update yet so sorry if these things are covered.]
4) Equipment guide or modern tech guide on what is possible given the tech levels in universe and what is not. Maybe a few ideas on what not to do because of future suppliment products.
MDC
MDC