In both world wars, the German army (Heer) was in many ways (though not all, like winter warfare) the best in the world. Their training, equipment, leadership, morale, staff system, creativity and initiative were wonderful, and produced excellent results at tactical and operational levels. In my opinion, their worst problems were always at the strategic level - production, logistics, and the top leaders, both political and military. They always ended up having too many powerful enemies and not enough powerful allies.
I don't think anybody could have fought better in the difficult conditions of 1918 and 1944 - 1945 than the ordinary German soldier.