I think you will find bomber command tied up lots of 88mm guns and men as anti air defenses.
If those guns had been free to be used elsewhere, the Russians would have got a kicking as their tanks would have been smashed to pieces.
Then there is all the ammo used for air defense of Germany, the resources used for that could have been used elsewhere and the war may not have gone the way it did. Wonder how many tanks, planes, ships and U-boats could have been supported by the resources used to defend against the 'threat' of bomber command.
The bombing offensive might not have achieved any measurable goals for a long time but it tied up German factories and men.
To be fair, Harris should have left Berlin and deep German targets well alone as he wasted so many men and aircraft for jack all damage. IT might also have helped if he hadn't been sporting and sent the raids down the same routes night after night
edit- Just remembered that Harris also liked to send the raids near German night fighter bases. The u-boats got a kicking due to technological advances later on in the war, Bomber command lost lot of men and aircraft by relying on duff wind predictions form the Met office, so either way, life for the crews of the u-boats and bombers sucked.
If I can find the book I read on the subject of bomber command during the war, I will post it up here. Its a sizeable read and very depressing in places.