Why 3 doctrines ?

Is it not possible to make 4 ?

Good question, but to make it fair its got to be 3. If someone had a choice of 4, then they have a better chance to counter something than the other players.

What more do you want, you have the Arty whoring(Offense) Doctrine, the Defense Doctrine, and the Tank Doctrine..

What you are requesting is this always repeted same stuff , but the Ostheer sould be realy realy new .

True, I would prefer a new strategy rather then the same one as the other 4 factions have. Although I consider Urban Combat relativly new and it is my favourite Doctrine.

I it a realy new doctrine and i find it great too. So hope the Ostheer will have some exordinery too.

because all the old countries (factions) have three doctrines   

In my opinion, all the factions have a doctrine to which is great for the three main types of players, the turtle, the blitz attacker, and the late game powerhouse. The turtle relies heavily on defenses and artillery, the blitz reliese on the momentum of his tanks and infantry to dislodge the person he/she is attacking, and the late game powerhouse uses strong heavy units that are only reasonable in the late game to come out on top. Now, the Urban combat for the russain faction is different from these three, because it relies on forcing the opponent to fear being in a building. This type of player is the siege, the nightmare of defensive players. The siege's role is to break the stalemate of urban combat and destroy any and all buildings in his wake. This is why the KV-2 (with its powerful but inaccurate cannon) is so useful in the urban fighting arena, it can pummel soldiers out of their hiding places.

Extremely accurate summery by Panzer. And one I would agree with. Not much can drive soliders out of buildings in this game but The Sniper ae, the KV-2, and the other fine additions.. Are some of those..

I just wanted to say that the Devs should make new kinds of doctrines maybe your these special player types but maybe different ways for early,fast and late game, so that you need not to be fixed at tanks for a good early game.( Of course ,the Ostheer needs something  for tanks.)