This kind of idea is some of what I am exploring in my TL.
The problem for making a united Germany in 1848 was that every side was unwilling to compromise their definition of 'territorial integrity'. Even for advocates of the Großdeutschland solution, the non-German populations of the Austrian Empire were going to be a problem, and iOTL once the Austrians beat down the Viennese revolt and restored control, they were absolutely unwilling to compromise any part of the empire being in any way separate, while the unifiers wanted Austria's German areas and not much else.
Add to that fact that the biggest faction at Frankfurt were mainly interested in seeing Prussia at the head of a united Germany, and Austria's got big problems. If Austria were to lose Hungary (and with it presumably most of its non-German population), perhaps the not pro-Prussians would rally behind Austria as a counterweight, as has been mentioned above.
It's certainly an interesting question, and I think would be a big boost to an earlier German unification.