That arrangement would be so Serbian heavy that the smaller groups would have no interest. I don’t even know how efficient Yugoslavia was at governance, because the member nations had a lot of parallel autonomous structures (which made it easier to secede when the time came).

But even with the particularities of the post-Yugoslav states, I think a lot of legislation/regulation is geared to mimic European Union laws as all these states hope eventually to join. Surely you’ll have some differences, but there’s a lot of streamlining in order to align with international institutions.