I'd argue Amarr worlds would be very, very heavily distinguished from each other by their distance to places like the Royal "home systems", major trade routes, borders, and of course Amarr itself.
To expand: "Higher" worlds such as the royal home systems, important systems such as Hedion, etc. probably have a higher concentration of Holders as many minor families and even the major ones come together to weave their plots, politik, and so on. In these worlds, sheer necessity of both limited space on the world and ability for commoners to easily be at hand to assist their leiges would demand at least some commoners live close to - if not immediately with - their Holders. I'm sure there would be some "commoner slums" (although even these are likely to be quite wealthy) as well as "Holders only" areas, but there would be more mixing than...
Frontier/underpopulated worlds: Here, Holders would have space to spead out and with no other Holders living next door, some Holders might isolate themselves from the "masses", holding themselves distant in great estates. Of course, this would be a general impression, not at all the absolute rule - in even more underdeveloped worlds, Holders and Commoners might have to live relatively close simply to take advantage of any defensive measures the colony might have.
