[revised 2 Jan 2021]
In the series of battles starting with Antietam, including Fredericksburg, and running up to Stones River, you should have caused 125,000-150,000 Union casualties. At Stones River there is an opportunity to cause tens of thousands more.
You bring three 20-unit corps, the first at the CSA left, the second at the center, and the last at the CSA right, all facing west to a long Union line running north and south.
Your corps should all be mostly infantry with some melee cav. Your main goal is to take two Union flag positions (Nashville Turnpike East and Nashville Turnpike West) situated well behind the initial Union line. You also should be able to trap and annihilate the entire Union force.
At the beginning push at the Union line, especially at the far right (southern) flank of the Union, with your left corps.
Slowly increase pressure from the east with your central corps when it appears; join this corps to your left corps when the latter gets close.
Use your left and central corps to take the two Nashville Pike flags.
Use your last-appearing right corps to run across the river, spread out, and crush the Federals from the north as your first two corps surge up from the south.
Lastly, use cav and a couple of infantry divisions to trap and destroy/capture stragglers, especially those that squirt up to the very top of the map.