From: Chicago, Illinois
I wouldn't pull out of Leningrad completely. I noticed you haven't fortified the "Back Door" hex at all, though, so you will fall quickly to siege if he reaches Lake Ladoga. If I am him, I don't bother getting to the Svir, and instead go straight for the Neva.
That being said, I would pile-on that spearhead along the Volkhov, and I would pull back out of the bulge to the West of that for the most part, though leave a line of units along the Rough and in front of Kolpino/Pushkin. There are a series of swamp hexes to the NW of that spearhead; have a unit in all of them. Make him fight to Ladoga. Don't worry about defending the spearhead to the SE, around Lake Ilmen; a Panzer thrust in that direction wouild be doing you a favor, and at any rate, they are fixed on Leningrad.
Make sure you get all the Cavalry out of that bulge, and over the Volkhov; those are the most valuable units.
But your're doomed up there regardless. I wouldn't send anymore reinforcements, because once Leningrad falls, you can just pull back into the endless forests up there.