My biggest wishes are related to immigration.
- People should be more willing to go to the colonies/dominions of their motherland. Large numbers of British went to Canada, Australia, New Zealand and large parts of Africa. In Vicky this just won't happen, or on a very, very small scale. It's event driven in VIP, but it shouldn't be. The same goes for other colonial empires ofcourse. The French will barely go to Northern Africa and so on.
- Provinces should have a population cap. Everybody knows the stories of Uruguay, Haiti or the USCA with 150 million+ inhabitants. Just not possible or realistic. The same goes for the Alaska Immigrant Magnet. Yes, people went there, but it's not really realistic.
- Immigrants should mostly retain their own religion. Nanfaren buddhist, Russian orthodox, French catholic, Albanian sunni, Ashkenazi jewish immigrants can all merge into Yankee protestants in the space of only a few days/weeks.
- With multiple national cultures, immigrants should assimilate to the dominant provincial/regional culture of the province they go to. So an immigrant moving to Texas or any Southern state will end up as a Texan or Dixie, but not a Yankee. There could also be a certain percentage, so some do end up Yankee, but I really think most should assimilate to the nearest dominant culture. With retaining religion and assimilating to dominant regional culture you won't get a Southern USA which is 80% Yankee. (These are all USA examples, but should ofcourse be applied to all nations).
- This one is a bit touchy, but here goes. I don't think Non-European/Western cultures should assimilate to a Western culture. Most European who immigrated to the Americas retained their european culture or assimilated and became Yankees, Dixies, Texans, Canadians and so on and so on. But for example the Chinese workers who worked on the railroads in the US weren't assimilted to Yankee. Here are two options. Either let them keep their Chinese culture or let them evolve into something like "Chinese American". The same goes for other non western cultures.