Could the Nazis have achieved control of the air, at least over their own territory? What impact would it have on each of the main threats?
V1 was a winner, forcing the Allies to deploy vast numbers of AAA and then air strikes on the V1 launch sites.V2 was a waste of time and resources.
The RAF will still becoming by night and by 1944 its far too late to save German industry. The weakness the Allies identified with the Me262 was that it could be targeted quite easily at take off and landing and with the sheer numbers of aircraft available to the Allies 'sweeps' aren't an issue. As has been mentioned the issue for Germany wasn't airframes, it was pilots and fuel. In 1945 OTL there were huge numbers of jet fighters being built and simply sitting on the ground with no one to fly them.V2 was a waste of time and resources.
More jets earlier means LW pilots make the switch from now under-performing 109s and 190s into over-performing fighters. That in return should mean greater losses to the Allied AFs and lower losses to the LW pilots & fighters, meaning also that losses to the German factories (especially the ones making fuel from coal) are not as destroyed in 1944 like they were per OTL.