[@ScorpionFlower] Making a new noble would be fine. They just wouldn't be as powerful as the three families. But I made sure to add upper class areas on the map of Rothenburg so there are other families of higher class in the city. There is also a large shopping district at the docks they could own a part of.

As of now, the three families have a large business in logging, property, and tax collecting as well as the Northern marketplace. So the shops located near the docks are either privately owned or you can create a noble who runs them. Ooooorr you could make a noble character who runs the docks, as that could be a fairly lucrative business venture.