By better I don't mean more, in fact maybe less territory but more strategegical one be better.
Green Ottoman Empire, yellow romanian vassals, and red hungary (vassal/ally).
The conquest and direct rule of Hungary was a waste of resources and an strategical mistake. Logistics didnt allow the ottomans to govern or defend the territory efficiently (both communications and tropes from Constantinople were to slow to arrive), so clearly the vast majority of Hungary should be prop as a protestant vassal to shield ottoman territory from the Habsburg, and probably help mitigate european reactions to Ottoman growing influence in Europe of instead of direct conquest, the OE projects its influence through a christian vassal. Also trying to cement their rol as a promoter and ally of protestantism in Europe would open them to more permanent alliances with some states.
But there is still some territories in the balkans that could be managable and worthy for the ottomans: Dalmatia and Corfu and the rest of the Ionian islands, Temesvar and Slavonia (all marked on the map).
Dalmatia and those islands are vital territory to to guaranteed ottoman hegemony in the Adriatic and the eastern mediterranean and to defend the western coeast of the empire, also there lightly populated rich provinces. The italian dalmatian cities would go to vassal Ragusa.
Trau, Splato and the islands in between surely would go to Ragusa and maybe Zara too, or maybe the OE decides they need a god port city on the northeastern Adriatic. The westernmost three could go either to Ragusa or vassal Hungary, depending of wathever the ottomans want Hungary to have a strong coast or not. The Ionian islands would be annexed of course.
Now Slavonia, the region between Bosnia and the Drava river. I don't know much of the region but I think after the conquest must of it was added to the Bosnia Eyalet, so it would make Bosnia larger, still allow them to keem a nice river frontier but thend towards the flat terrain unlike bosnia but communications must be ok and still gibs better strategical deep to Bosnia.
Now Temesvar:
It has a river borders so I guess that must help with communications and defence. Also its majority serbian and romanian orthodox but hungarians and germans were quite capable in expanding their minorities there so I guess the ottomans should be able to create muslim and hungarian protestant plurality in the region. But the most important thing it gibs strategical deep to Belgrade Pashaluk, which was historical low in population being the area of entry of Habsburg armies and the starting point of Austian supported revolts, both thing that first resulted in lots of violance against muslim which the ottomans would later return whit violance againt the orthodox population, not to mention being the place of battles between the two, all that keep the population low. Being better protected would mean that more muslims would arrive and live there and the serbians would be less prone to rebelion, also the place wouldnt get burned down in war every few decades.
Now the most important thing is to achieve a strong Hungary to act against Habsburg ambitions. Letting this Hungary control Croatia proper to give them a coast and servinf as a sanitary cordon between ottomans domains and Habsburg lands. If Hungary exists and is under christian rule (though protestant) I guess there would be less alarm in Poland and Russia, and maybe pass as Ottoman interference in disputes among christian rulers rather then muslim rule expanding into central europe, so maybe it would be less likely for them to interfere if the ottomans help Hungary "regains its western domains and sack Vienna". But more importantly it would give the ottomans a strong christhian ally that could project power in the pannonian basin and defend their borders.
Could the ottomans achieve this and keep ot long term? What would be the ramifications of a less expanded but better defended ottoman europe?
Green Ottoman Empire, yellow romanian vassals, and red hungary (vassal/ally).
The conquest and direct rule of Hungary was a waste of resources and an strategical mistake. Logistics didnt allow the ottomans to govern or defend the territory efficiently (both communications and tropes from Constantinople were to slow to arrive), so clearly the vast majority of Hungary should be prop as a protestant vassal to shield ottoman territory from the Habsburg, and probably help mitigate european reactions to Ottoman growing influence in Europe of instead of direct conquest, the OE projects its influence through a christian vassal. Also trying to cement their rol as a promoter and ally of protestantism in Europe would open them to more permanent alliances with some states.
But there is still some territories in the balkans that could be managable and worthy for the ottomans: Dalmatia and Corfu and the rest of the Ionian islands, Temesvar and Slavonia (all marked on the map).
Dalmatia and those islands are vital territory to to guaranteed ottoman hegemony in the Adriatic and the eastern mediterranean and to defend the western coeast of the empire, also there lightly populated rich provinces. The italian dalmatian cities would go to vassal Ragusa.

Trau, Splato and the islands in between surely would go to Ragusa and maybe Zara too, or maybe the OE decides they need a god port city on the northeastern Adriatic. The westernmost three could go either to Ragusa or vassal Hungary, depending of wathever the ottomans want Hungary to have a strong coast or not. The Ionian islands would be annexed of course.
Now Slavonia, the region between Bosnia and the Drava river. I don't know much of the region but I think after the conquest must of it was added to the Bosnia Eyalet, so it would make Bosnia larger, still allow them to keem a nice river frontier but thend towards the flat terrain unlike bosnia but communications must be ok and still gibs better strategical deep to Bosnia.

Now Temesvar:

It has a river borders so I guess that must help with communications and defence. Also its majority serbian and romanian orthodox but hungarians and germans were quite capable in expanding their minorities there so I guess the ottomans should be able to create muslim and hungarian protestant plurality in the region. But the most important thing it gibs strategical deep to Belgrade Pashaluk, which was historical low in population being the area of entry of Habsburg armies and the starting point of Austian supported revolts, both thing that first resulted in lots of violance against muslim which the ottomans would later return whit violance againt the orthodox population, not to mention being the place of battles between the two, all that keep the population low. Being better protected would mean that more muslims would arrive and live there and the serbians would be less prone to rebelion, also the place wouldnt get burned down in war every few decades.
Now the most important thing is to achieve a strong Hungary to act against Habsburg ambitions. Letting this Hungary control Croatia proper to give them a coast and servinf as a sanitary cordon between ottomans domains and Habsburg lands. If Hungary exists and is under christian rule (though protestant) I guess there would be less alarm in Poland and Russia, and maybe pass as Ottoman interference in disputes among christian rulers rather then muslim rule expanding into central europe, so maybe it would be less likely for them to interfere if the ottomans help Hungary "regains its western domains and sack Vienna". But more importantly it would give the ottomans a strong christhian ally that could project power in the pannonian basin and defend their borders.
Could the ottomans achieve this and keep ot long term? What would be the ramifications of a less expanded but better defended ottoman europe?