They would have been able to solidify their holdings, plus the real target was not Moscow but the Ukraine and Ploetsi Oil fields to have the energy resources to wage war. You see some things never really change.
Forcing the Soviets to abandon territory back toward Siberia would have made counterattacks tough.
You mean the oil fields in the Caucasus... which the Germans tried to get in 1942 but got sidetracked into the Battle of Stalingrad. Which was the end of German offensive operations in Russia (well, except for Kursk).
Ploesti is in Romania.