Excellent work so far! All of your efforts are rapidly approaching a crescendo.
Now that you are north of the Volga in force, I see a significant opportunity in the North that is practically beginning to be exploited. Bear with me here, and please tell me why this would or wouldn’t work...
I see two salients at this time: the Moscow salient, and the Cherepovets salient. Both are supplied by a single rail line. Both have significant overextended forces (I count approximately 40 or more divisions on frontlines West of Cherepovets!) Both salients’ rail lines are relatively close to your spearhead MLRs (The Cherepovets to Voldoga rail section is 70 miles to interdict, and 80 miles to cut! Compare that with Kovrov which is 60/70 miles respectively.
A further look at the situation in the North is where the real gold lies. Despite the interruptions to the rail this turn near VV, the northern spearhead is capable of being better supplied at the current range. A lunge to cut the rail would only be moderately far from rail, and would disappear if a path can be drawn to Finnish lines. And a most critical difference, the enemy is not dug in along the path to cutting the northern rail! Consider the enormous rail transport cost involved in bringing in troops to cover your advance. Also consider the fact that half of the Soviet forces West of Cherepovets, in the SouthWest, are too far from rail for immediate evacuation. Even if evacuation was possible, all of this rail use, combined with the reinforcing of Soviet forces to prevent cutting the rail, brings these two things away from Moscow to a less important part of the front.
Ironically, this is a distraction that will benefit you more: you have the initiative; he has to react without fortification to help hiim; it will cause mass panic on his northernmost frontlines; and you otherwise have a very low ability to reach Kovrov from a northern axis of advance; so a Cherepovets offensive would be a effective use of their positioning.
I don’t know if my proposal is radical to you. But I am begging you to consider. I understand that a low resolution understanding of the front would be critical of diverting troops from an encirclement on Moscow, but I hope I have convinced you otherwise. I will leave because I have said enough. Also I am on my phone.