I think the middle power is a bit weaker, but it still is pretty balanced. It comes down to how many centers are reachable in the beginning. Everybody has a chance at two neutral centers (well, west has a chance at three but not realistically all at once) and some of the home centers of the others. The first year has either some bounces, which then allow to take neutral centers in autumn, or missing the bounce and ones home centers being in danger - but one also having a shot at somebody elses center. It's a gamble then, but over the different options chances equal out. In 1066 this is not the case, England an Normans are close together and often have to defend home centers (Normans especially, it's very likely that it won't be able to savely take a center in year 1), while Norway can guarantee a center and also be annoying to England. In Verdun, everybody could take from everybody, in 1066 nobody can take from Norway, Norway could take from England. (I played both maps mainly on gunboat. Press probably evens the chances a bit as the two weaker powers can ally against the strongest)