I mostly accounted for the main trumps of the game, but we shouldn't forget other aspects of it, which have also been well devised. Their names are self-explanatory, and when you destroy them, their ruins will remain on the map. You can also set fire to your own buildings, which can prove to be very useful both when retreating and in sabotage. A cool lookin military camp. Two lonely ships cruisin' The unavoidable tech-tree is that big that you will rarely ever get to research all technologies in one session.
All technologies are easily accessible and come with detailed explanations of all they do.
If I would just stop now, Cossacks would turn out to be one of those perfect games, but several flaws, unfortunately, hinder this. First, your computer opponents will frequently use the rushing tactics, thus simply annulling all conceptual advances this game brought. Rapid production of small, cheap kamikaze units and using them to attack fewer far more powerful units still works. I guess this kills all need for subtle tactics in the game. Even beside this, enemy AI is far from perfect and will sometimes react slowly, if at all.