The thing with Austria- Hungary is that they needed reform, but reform would kill them. What I think the Habsburgs would do after a successful WW1 is probably kill themselves. I think they would be scared shitless by all increased demands from autonomy and the Hungarians becoming more cocky every second. So they hit the panic button and dissolve the Vienna and Budapest parliaments and try a centralized dictatorship. Buys them a year or two, before it all comes crashing down with everyone rising up against them.
Resulting in a Communist/Socialist Union of Danubian Soviets?
Also Hungary was all talk and little else. Their planed demands for 1917 didn't have that strong a footing, at the first wif that Hungary is leaving Croatia will be fighting tooth and nail of going away alongside Hungary unless Hungary agrees with an independent Croatia.