I'd love if we could have a setting that prevents AI countries from releasing countries they conquered - I think its a bit immersion breaking to see France release half its colonial territories as independent nations before the start of WW2, or Germany release the Netherlands just a year after conquering them, etc.
It is not problem with releasing countries, but with the frequency and context of doing this.
If Germany or UK conquires Netherlands, it coul'd release it right away (to simulate installing friendly government and making ally instead enemy) or to annex it. It is highly unlikely and unrealistic that Germany woul'd release Netherlands a year after or as the time passes by...
Second case is when two regions are in war with each other and one of them gets territoryy that has loyalty to third region (e.g. UK pushes Germany out of territory annexed from Netherlands. In that case, AI might "liberate" Netherlands by releasing it and installing friendly regime by doing that. I'm not sure if AI can be tought to behave in this manner but anyway the frequency at which it releases territories might be lowered and might depend on some other factors (such as percentage of loyalty, economic situation, lack of resources, taxatioon...)
