I actually quite like the idea of newly conquered areas getting its soldier pops demoted into farmers or somesuch.
+ bureaucrats.
Colonies are overrated in V2. Most colonial powers were spending a lot of money just to support the colony which produces valuable or strategic good. But in V2 you can just easily colonize the whole Africa, turn in into states (well, not all colonies, but many), build massive industry, hire huge tanks&planes army...
V2 isn't supposed to be that kind of game. It's not some futuristic space strategy, it's based on history, where we could definitely say "there was nothing like this".