Zincat, I agree on part of that.
Japan is certainly a force to be reckoned with as they just showed in the last war. It will be interesting to see where they go with it.
The Commonwealth is a superpower without a doubt BUT that all depends on their future relations with these new aliens. If they are friendly and can even ally with them, or the war they have is easy and over quickly as a complete victory for the Commonwealth, I imagine the Commonwealth would be pretty well unstoppable. If the war goes poorly it will sap a lot of their power, though they can pretend since they won't tell the other powers about the new aliens if anyone tries to call such a bluff the Commonwealth might collapse. The worst case scenario is if the war goes disastrously in which case they will have to call all the other powers in, or at least a few of them, and will have to give up major concessions plus whatever they lose to the new foe.
The US could really go either way in my opinion, they have carved out their section of the expanding sandbox and its just a matter of how they go on from here. The US occupies a top spot but its going to be a bit more difficult for them to expand and they alienated a good chunk of the international community in the last war.
Russia has been so quiet for so long its hard to gauge where they are, especially compared to the other powers. France has that issue too. They are both off doing their own thing in what I imagine is comfortably second tier power-wise.
If Germany can solve its problems regarding fuel, and in a few years they will at the outside, I think they are set to sit at the big boy's table that the Commonwealth, US, and Japan sit at. Its just a real question of how long will it take them and how much ground will they lose in that time.
I think the Second Colonial War will solidify the tiers of power, as it will any of the following.The minors fighting over the left over scraps and have a two tier system with France, Russia, Germany, Japan, the US, and the Commonwealth at the higher tier and everyone else at the lower one. France, Russia, Germany against each other, which will push the winner(s) into the top tier and the loser(s) into the bottom, again with a two tier structure. Or the minors against one of the larger powers which would set up a three power tier set up.