Regarding your Stonewall Jackson, you ‘ll get no real disagreement from me.
There’s been a long running “If only Jackson were alive on the first day of Gettysburg, everything would have turned out differently” line of thinking out there.
Is it possible that Jackson would have captured Seminary Ridge? Yes it is. It’s also just as possible that his performance that day could have been very similiar to that in the Seven Days campaign. If it was the latter, then the answer would be No.
Frankly, I would rate Longstreet as highly as Jackson, even though the former’s ego sometimes got him into trouble and he too occasionally had feet of clay. But at least he was smart enough to see the tactical value of the Round Tops, even if it was a day late and a dollar short.
They mystery to me is why Lee — ever the brilliant tactician — dismissed them.