You underestimate Grant, just like so many CSA generals did to their rue. If Grant had commanded during the Gettysburg campaign, Lee would not have been able to concentrate before Gettysburg. Grant would have dominated the central ground and defeated each of the extended Confederate columns in detail. His campaigns in Missouri, Kentucky, Tennessee, Mississippi, and Virginia speak for themselves. Lee's greatest strength was his also his greatest weakness, as Pete Longstreet had no hesitation to discuss after the war: an offensive spirit that ignored the reality of CSA's capacity to wage war. Lee fought battles while Grant waged war.
FYI, England was advising Lincoln and Lincoln passed it on to Grant. England had a vested interest in maintaining control of the northeast because it feared "the new country would collapse". England wanted the tax monies, and the makings for their whiskey and control of the country.
The north did not win the war, and you'd know this if you actually studied the matter. Lee was betrayed by one of his own advisors and unknowingly walked his men into a killing field. That is exactly when England ordered Lincoln to stop the war, Lincoln declared the war won by the north when in fact it was the South who won. Of course, the harpies in the north were furious when Grant simply sent the Southern soldiers back home, so furious in fact that the scum made a cemetery of dead norther solders in Lee's front yard. (Personally I would have dug them all up and dumped them somewhere on a New York street corner.)
Why did England order the halt to the Civil War? England stated and this is a quote "if you (Lincoln) don't stop the war the Americans will keep fighting until they are all dead". England was alarmed at the death rates.
Lee and Grant fought together prior to the Civil War.