With Egypt seized, they would also have to clear the British from the Med, whcih would take a while, possibly. An alternative might be the 'Fuhrer versus Abdul' scenario, with Germany invading or forcing an alliance with Turkey, and going after India from that route. However I think Stalin would react to that. In fact the Soviets would think a German attack on India was a dream come true - a substantial number of divisions at the end of a very long supply line a long way from Russia's centre. They could invade into Persia or Turkey and chop up the Germans, or simply go straight for Berlin.
Fuhrer vs Abdul!
Strangely enough I was thinking of something similar last night.