Attributes, relations and FlexiFields make the model radically fluid — and hard to pin down.
Unit4 treats almost everything as an attribute with relations, so the same construct can behave as a dimension, a master record or a rule input. D365 F&O demands that each of those roles be named explicitly, which turns Unit4 migration into a classification exercise before it becomes a data exercise.
Account rules + attribute relations → Account structures + posting profiles