Austria and France are too powerful.
with support from England and the dutch its not. After all Hungary and even parts of Austria Proper were rebelling or begging to rebel around the same time, none of them were however as organized as the Bohemians.
Honestly Denmark joining the war earlier could give the Protestant League a clear leader and they could centralize their forces better. If somehow Sweden too got involved Austria is Royaly screwed. France doesn't care to watch on of their greatest rivals get the shit kicked out of it they helped protestants out OTL anyhow (i think that was because of Louie XII though). It still wouldn't be easy and Austria would probably still retake Bohemia but eventually the Protestants could take it back.
If Austria wants to remain a great power (they were already clearly split with Spain in the "interest" department) they are going to have to give up eventually to put down the Magyar protestants.
That's probably too late. By then there are too many Hohenzollerns
Good points, however Fredrick line is almost empty i do believe besides his beloved nephew, the Great Elector. If the war ends with bohemia and the palitinate in Freddy V's hands and then his line somehow dies off going to Fredrick Wilhelm I then a unification of Germany would probably occur under his son or Grandson.
You can't tell me a country can't rise to prominence Because they are small and surrounded by larger powers, because Sweden, Prussia, the Dutch all did it.