Family register is probably unique because it basically functions as everything that'd be kept track of separately in the west. You get a certificate of birth, your marriage is registered separately, the place you live is a different bureaucratic systems, religious stuff is separate again and so on. But a family register gathers everything in one spot (with all the advantages and disadvantages of that).
Mino is a turning point in Nobunaga's campaigns. It'll be interesting to see whether some ahistorical stuff happens or whether for now things follow the historical route.