Grant was good at turning the handle on Lincolns meat grinder.
Grant was IMHO the greatest general in American history. Yes, he knew how to use superior numbers when he had them, but he knew how to win when he didn’t. You only need to look at his Vicksburg campaign. He deliberately split his army, and put himself in the position of being surrounded by superior numbers and cut off from resupply, because it was the only way to get to Vicksburg.
I think Grant along with his friend Longstreet were two of the first truly modern generals in history, in that they saw who new technology like railroads would shape the strategic picture. Both their memoirs are great reading. Longstreet writes about his plan to relieve Vicksburg by sending half the Army of Northern VA to combine with the Army of Tennessee and the Army of Mississippi and invade north into Ohio. In May of 1863 he said by using railroads and taking advantage of interior lines of supply he could put an army of 100,000 at the banks of the Ohio river by July 4th (which just happened to be the date Vicksburg surrendered. That would force Grant to end the siege and move north to stop him.
It’s an interesting “what if”, but he never offered his plan because he learned Lee had already submitted his plan to invade Pennsylvania.