Longstreet argued for a flanking movement to the South around the Little Round Top redoubt instead of an direct assault on the Union position.
I played that hand in a war game on several occasions and won every time.
oh yeah....they could have marched to Hanover if they wanted too around the right of the Union flank. but a combination of the Napoleonic School tactics (i.e. we will fight our enemy before us), and the fact that Lee wanted to defeat the US man to man (they have said his heart issues were getting much worse as 1863 was wearing on), mitigated that.
It is a given that had Jackson been there and not AP Hill, it may have been much different.