Did Hitler count on his allies (Japan, Italy, Romania, etc.) to actually do anything helpful in the war effort? Or had he dismissed them as incompetent, unreliable, etc.

Well the German army wasn't formed only of ethnic German soldiers, it had Romanians Hungarians, Polish , you name it. Also Romania for example fueled the Germans with Petrol (Ploiesti oil fields) and grain (Romania was known as a powerful agricultural country).