Alright, I lied - I did find time to work on this. It was bothering me too much.
I've rolled with MrBenn's idea of adding something along the lines of the old East India Trading Company. Now to whallop one of the colonies, a European player must first take a killer neutral trading company... killer neutral because the government doesn't actually own the trading co, though they had a great deal of influence on them. And the trading companies still can't actually invade and conquer, they can only knock out the colonies. I'm not really thinking that the trading companies need any more than a 3 neutral value - they are already dead ends, as they can only bombard and are lost each round, so using them will mean expending some serious resources.
Here's my rationale behind this, though I'm sure somebody will present an excellent counter-argument and it will all change by Monday: early feedback on this map suggested that Europe should hold some kind of value or have some kind of power above and beyond those of the rest of the world, because it is in Europe that the imperial powers of the day were centered. This map is intended to represent the gradual decay of those empires - they should still be able to exert influence over their colonies, but direct control is slipping away. And influence was generally exerted through an intermediary - the Trading Co's. I think that this set-up reflects Europe's ability to affect the world, if not entirely control it.
Could play become frustrating for the player who holds the colonies? Yes; to which I say welcome to the real world, sweetie pie. It sucked to be an African or Indian prince in 1910, because no matter how hot your shit was there was little chance of securing your homeland for your people for very long.
Ultimately we'll have to play with the bonuses for the regions that can be bombarded - make it worth somebody's while to go after Africa and Southeast Asia.
In other news, I removed the French flag from north africa, since France already has an attack route there.
I've also taken out the capital bonuses for now... I can really go either way on this one, and I think that giving the European powers a bonus in addition to their trading company powers is enough. This means the capitals don't need to start neutral. I also need to recount the territories now that I've added the ships.
And nobody can attack a trading co other than the home territory - it would never make sense to since they revert to neutral anyway.
Mountains - I'll deal with that later. Let's figure out how to play this.