I have not yet played with the national advantages, but I think that a colonial garrison changes completly the first turn strategy. A colonial garrison in India forces Japan to react by building Two IC on Asia during the first turn. They cannot afford to wait or they will see their presence in land threatened by India and a possible US IC (and the free infantry) from Sinkiang. Do not forget that Russia may “gang up” all its infantry in Buryatia SSR. This may seem ridiculous, but Russia has nothing to lose, they are protected by the Non-agression treaty. Russian Infantry only have to wait for the right moment to attack Manchuria and acquire some IPC.
This colonial garrison changes the aspect of the first turn, and it really help out UK’s player to have more fun and more power in the game.
It is clear that UK possess the best national advantages because each of their advantages is really useful. It is obvious that those advantages overcome other nations advantages…