Even playing Prussia/NGF/Germany or Austria, I tend to be somewhat conservative in terms of using the army. Potential objectives need to be weighed in terms of value versus cost. In a typical map-painter, as long as I win the war, there is no "cost"; in V2, those recruits come directly from your general population, and can return there, so they matter.
Ultimately, what makes V2 so enjoyable is that those pops (your Accepted Culture pops in particular) are an essential asset, your own people, and are not to be casually tossed away without some pressing need to prevent some even bigger disaster. In most other strategy games, your recruits auto-respawn, and losing a few thousand, or a few hundred thousand, has no effect at all on your working population. In V2, those soldier pops come directly from your farmers, laborers, and craftsmen who pay your bills and produce your resources, so losing them hurts you in the long run. As a result, in most games I don't care about casualties, as long as I don't have to rebuild the unit from scratch, while in V2, every lost soldier is a reduction in the strength of the country I'm playing, and I DO care about them, at least while the game lasts. That sense of playing a "benevolent" leader, protecting his people against outside aggression, is a big part of it.
That's not to say that I don't fight wars, but I try to avoid unnecessary wars, particularly those that will result in high body counts for token gains, and limit aggressive actions to taking only what vital resources I can get with minimal casualties, or else retaking core territory to regain and protect more of my own pops, as I see it.
My occasional map-painting romps to "practice warfare" with some random country tend to get dropped after only a couple of decades of play, because ultimately they don't feel either realistic or satisfying.