Lets say A-H managed to reform, and survivied till today. wheater thats possible or not, is not part of the question here.
How many inhabitants could German Austria have.
http://upload.wikimedia.org/wikiped...nic.svg/2000px-Greater_austria_ethnic.svg.png
OTL Austria is rather sparsely populated and only has a population of 8.440.465 people. If Austria would have the density of switzerland, there would be about 16 mio. inhabitants.
OTL Austrias population grew from 4,52 mio in 1870 to 6,76 mio in 1913.
North Rhine-Westphalia had a roughly 5 Mio. inhabitants in 1880, today it has a population of nearly 18 mio.
Bavaria had about 6 mio. in 1900, today it has 12 mio.
Do you think such a growth would be possible for Austria too ? Remember that Austria would be part of a big federation in this timeline, Austria would be a industralized region, so there could be many immigrants too, i can also imagine that German Austria would be quite urbanized, with a majority of the people living in cities, also most people would most likley live the flatter areas of Austria in the east.