Didn't notice that. Maybe it's not Hanover but Oldenburg.
I also see that Silesia seems partitioned along the Oder between Austria and Russia, while Prussia, or whatever it is, has actually got Lusatia from Saxony but NOT the rest of the Saxonian lands.
OTOH, saxony has somewhat got most of Hessen. Maybe the POD is in 1864. Prussia goes alone at war with Denmark and goes to take it all. A coalition is made to counter its expansionism, including Russia, Austria, Bavaria, Hanover and Saxony. The other German states side with Prussia. At the beginning the Prussians win some battle and occupy Lusatia and Hanover, then they are defeated and ask for terms, but are still strong enough to keep Denmark, Lusatia and half Hanover. Their german allies are totally steamrolled and given to Saxony and Bavaria. The latter must have fared very good in the war, which should be explained in some way: OTL's bavarian military was nowhere so fine.
Still, i can't see a reason in the universe why Prussia would ever prefer keepinh Denmark than Silesia.