I still play EUIII on and off and for that price you can't really go wrong.
I don't have divine wind, so can't say anything about it from experience but reviews weren't raving iirc. EU III comes standard with a world map, I think Divine Wind added start support for civs in Japan/China including some scenarios for that.
EDIT: Just saw that they also released 2 sprite packs for Divine Wind at € 1.99 each. Paradox is getting on the DLC cash bandwagon as well it seems.
Still a pity Divine Wind is 7.50€ seperate as well, not paying that kind of money for it when I already own the rest of the game.