Vlad the Impaler contains Ottoman expansion

What if Vlad the Impaler kept his throne from his second reign until old age and prevented further Ottoman expansion into Europe?

The Polish-Lithuanian Commonwealth, Habsburg lands, and Holy Roman Empire would face less Ottoman pressure, changing both their alliances and their internal sources of cohesion.

The scenario assumes that Vlad keeps his throne from his second reign until old age and prevents further Ottoman expansion into Europe. That would change the pressures acting on the Polish-Lithuanian Commonwealth and the Habsburg lands. The Holy Roman Empire would lose an external threat that helped encourage cooperation at critical moments. Warfare against the Ottomans also provided military employment for younger sons of ruling families, so removing that conflict would have consequences within those families.