I think we went over this in IRC.... but anyway:
in the next release in the building, vehicles, and weapons .txt's, we will set the owner to B. however the weapon/unit/structure will still need to be made available thru the tech tree.
This way, mods to sheets.vol can be made entirely thru a tech tree, without needing to touch any of the other files.
(BTW: you say you can't edit fire rates and other attributes thru a tech tree - you can however using the UNIT_PROP keyword to set the property differently. ask me if you need help, PlayingOutpost.)