[@POOHEAD189] To answer both of your questions: 1) The line of succession goes down from the main family line. So, The heir and person supposed to be now in charge of the house would be Nalia. However, since she is kind of off doing who knows what, yeah, Fiona and Lorenzo are pretty much going to be trying to solidify their own control of the house.

2) You can feel free to be from an existing house, just make sure to PM about which one and I can give you some extra back ground info and what not. If you wanna make your own house, also awesome! There were ten Great Houses before the plague and assassination of The Patron and his family, so, you being from one of the houses no longer in existence or just no longer very relevant would be completely reasonable. 

Anything else I can help with?