Grant is epic. But it was the machine of the northern navy and railroad logistics, that Grant used, that won the Civil War. It wasn't a struggle of personalities. The northern economy handed Grant one tool after another, and he used them as any common sense person would do.
I believe the issue was very few had insight how to utilize advantages the Union army had against the Confederacy, especially in the East. What seems like common sense today might not have been too obvious to the people at the time.