Re: provinces: trading them is easy.
I tried the province acquisition game with the Danes. Turn 40 and 14 settlements and a solid economy. Almost too easy.
I am trying to buy out the HRE one province at a time. It seems to work. At 40 turns HRE is now at 4 (Bologna, Metz, Staufen, and Frankfurt). I had to purchase Brelau, Innsbruch, and Nuremburg. No one has taken Bern?!?
Hungary was giving me problems so I captured Vienna and then traded it without military structures plus some florins to the Poles in exchange for Thorn. Sealed me off from the Hungarians and then I grabbed Bucharest for the ceasefire. This can be trade bait for the future (for what I do not know). It might come back to haunt me, but the Polish trade solved the immediate problem and added another settlement to the Danish lake project.
The Russians have only their capital and Moscow. No trading posibilities with them. I guess I will need to complete the Danish lake the old fashioned way.