There is something in a name. Superman is obviously a good guy and Painmaster McKillface is a bad guy. Darth Maul's mother never figured her son would grow up to be the head of the Jedi. The same thing is true for “Europa Universalis” - it's going to be about Europe and what it did.
The engine in “Europa Universalis 3” (EU3) is very powerful, however, and allows one to play as any of a great number of countries, many of them not in Europe. After a few playthroughs as the major (and minor) powers of Europe it can be fun to play a few games as China or Japan, or some of the other Asian contenders. The problem with this in the game is the same as the problem that faced the non-European powers in real-life: no one could could keep up with Europe's technological, economic or social progress in this period. Playing a non-European nation is tantamount to just waiting for a European nation to invade. The only alternative is to rush your nation into the “Westernization” event as soon as possible, thereby becoming a European nation in everything but location.
“Divine Wind”, the fourth expansion to EU3, attempts to remedy this situation by fleshing out Japan and China. Both countries are divided into smaller units at the beginning of the game. China is now split between different factions which vie for power within a sort-of unified country while the player has to juggle them around to gain their various bonuses and avoid their penalties. Japan is divided into 4 warring pseudo-countries which the player has to unite through conquest to become Emperor. The effect is to make these countries work more like the Holy Roman Empire. Simply making them function as a unified entity is a subgame in itself.
This works well as far as it goes. The only real issue is that it doesn't go very far. These unification issues are pretty much limited to the early game. If you haven't unified Japan reasonably early on be prepared for minor power status for the rest of the game. After unification it becomes the same old game – westernize as fast as possible or become a colony.
While it is nice to see them get their expansion in the sun (it's a “Victoria 2” joke, get it?), the Eastern countries are not the only things that get some attention in this expansion. A few are fairly minor – better graphics, more play-balancing, new achievements – but some deserve a deeper look.
The nicest improvement is the simplest. The player is now presented with the actual world map when negotiating a peace, and can see and choose which provinces to offer or demand. It was a never-ending source of frustration for this reviewer in the earlier versions of the game that he would only be presented with a list of provinces and no idea where they were. Being able to see directly what is at stake is immensely handy.Another nice-if-minor enhancement is to the province improvements menu. When building an improvement in a province the player is now displayed with a matrix of all possible improvements. Valid improvements are in color, unavailable ones are grayed out. Each row corresponds to a type of improvement (e.g., religious, land force, taxation) while each column displays improvements in increasing level of sophistication (e.g. harbor, docks, shipyard, starport). This is very handy when planning out development.
Magistrates are now more important in that it requires a magistrate to build province improvements. On the one hand this slows down the old “I just discovered how to build roads, now I have to click on every province I own and build a road in it” phase that would bring the game to a standstill of clicking. On the other hand it just turns it into an “OK I have another magistrate now which province(s) haven't I built a road in yet?” micromanagement fest. This is not better.
Hordes are now tougher. They are tougher to deal with diplomatically, and tougher to push back militarily. They are tough for the organized nations and may be too tough for many of the smaller eastern European nations they face early on. They are best faced by the player who wants to focus on war rather than economic development.
Trade range (how far away your traders can travel) has been shortened, and the effects of the trade winds have been strengthened, reinforcing the limitations on travel in the time period. This makes games turn out more historically-reasonable without straitjacketing the player.
Also, sadly, you are now limited to one of a given type of advisor at a time. No more running up a bad reputation and then hiring three philosophers to bring it back down super-quick. Add to that a new, faster rate of decay for cultural tradition and the advisor system works much better.
There really isn't much bad to say about “Divine Wind”. One could complain that the African and American countries still do not have much to do, or much chance of holding off the Europeans, but they really didn't in the time period the game covers in any case. They might make for an interesting mod or an entirely separate game but there does not seem to be a reasonable way to incorporate a powerful Native American empire into EU3 while having it remain a (semi-)faithful historical simulation.
This is the fourth expansion and contains nothing really revolutionary, for good or ill. This is about the end of the road for EU3 as a “living” game (although the mod community will be active for years to come). Any radical new developments will have to come from “Europa Universalis 4”. It has been a good run.
In summary, “Divine Wind” adds some content for Japan and China, implements some interface improvements, and tweaks gameplay a bit, but does nothing dramatic. It is a good purchase for fans of the series but won't convince anyone who doesn't already play EU3 to try it.