The idea of a halt in German operations in the Center after Smolensk, with Typhoon being cancelled in favor of rest and recovery is a simple POD which could feasibly be worked out provided Hitler believes that an advance on Moscow in the fall would prove ill advised. I don't think it's a stretch to say that he could have come to that conclusion. So let's look at the pros and cons of such a halt:
Pros:
1. Manpower losses are certainly less than those sufferd during Typhoon.
2. German strategic defensive position is better, with fewer salients and awkward twists and turns.
3. Infantry divisions can be better distributed along the front.
4. Logistics can to some degree be improved.
5. Divisions have time to entrench and rest.
Cons:
1. A halt essentially hands the Red Army the strategic initiative without a fight. Even with German tactical superiority this is a bad thing.
2. The Red Army will likely launch counteroffensives. Not very succesful ones, but they will be very costly and irritating for both sides.
3. The Red Army wins several valuable months to regroup. Rather than losing multiple fronts during Typhoon it can recuuperate essentially unchecked.
4. Several hundred thousand men lost during Typhoon, along with equipment, remain availiable for use.
5. The Heer cannot halt operations along the entire front. In the center yes, but not in the north and south. Thus counteroffensives will still strike overextended forces in those areas, ever moreso than IOTL.
6. The Red Army as time to plan a counteroffensive. IOTL the Moscow counterattack was designed first and foremost to drive the Germans from the outskirts. Only a month later was it expanded into an attempt to destroy Center as a whole. So instead of planning as it advances, STAVKA can conceive an operational design without having to rush into an offensive.
So while a winter halt does help the Heer, it greatly speeds up the Red Army's recovery. Both sides benefit equally from an operatonal lull. Further I'm rather critical of the idea that the heer can critically improve it's supply situation in time to properly equip all units and supply them. Better than OTL, but not to the degree that it has a decisive impact.
In conclusion the Red Army will likely drive the Germans from the region east of Lenungrad and the Rostov region as per OTL. Further counterattacks will see the Germans lose key portions of the western Donbass. The Leningrad blockade may also be loosened earlier than OTL, but the region's geography prevents the Red Army from achieving any effective victory until much later. Center will come under the heaviest pressure, especially 2nd Army and 2nd Panzer Army, along with 6th Army further south. The Red army will take the line of Kharkov-Oboian-Kursk-Orel-Briansk but will stall before further gains can be made, except in more local salients. Other parts of Center and south will also buckle, but there will be no Toropets-Kholm breakthroughs. Losses will be very heavy on both sides; not as bad as OTL but still crippling for the Heer in the long run. By Spring the Red Army will have achieved noticeable advances, but just as IOT the Heer will be ready to resume it's advance. Oddly it's target will likely be Moscow, the most realistic target due to the defeats in the south.