Zuflucht would be an unimpressive world if it wasn’t the spinward gateway to the Islands. It is technically independent, but has a strong Imperium presence. There are few laws on this world, and few protections for off-worlders.
One of the major powers of the Islands, Serendip Belt is a belter culture strongly bound together with their social identity. They value politeness, skills and competence, and strive hard to be good at what they do in order to better fit into that society. The pressure to find a valued place in that society can be tough though, especially when robots dominate much of the labour force.
Topas is simply described as a single radioactive desert, where people shelter in the ruins of war torn subterranean cities. The atmosphere is too thin to breathe, and water is almost non-existent. The cities are ruled by a single huge bureaucracy that stifles free enterprise, and strictly controls the distribution of power, air, water and food.
Neubayern is a world of grand architecture, a liberal society with harsh laws with a strong concept of state and society but very little thought towards privacy. The state draws a harsh line when it comes to those who try to take advantage of their freedoms to harm others or damage the state, and its police forces are well funded and not very gentle. And that is how Neubayerns like it.