Poland would still remain Po(or)land.
No more Croats thats for sure
wouldn't be possible to reunite them in any way
cant' happen when people still think in nationalistic terms.
austria-hungary worked when people still thought more or less in imperialist terms.
you can say about imperialism what you want, but as a stateform it's much stronger than nationalism. nationalistic countries tend to be very small (even germany is smaller than the HRE).
look at ottoman caliphate/empire. it collapsed bcz of arab nationalism lol. look at central europe what a stinking mess it is. Czechia is really weak now. bohemia was fucking strong lol.
bohemia was like OP. what are the nationalistic countries that came out of bohemia? all small bites for russia lol.
If we keep Austria well fed they won't get Hungary.