Agree about actual deployment of Corse's Virginia Brigade.

Just my opinion, but ---
It would have been better to send Corse and his men with Lee. In their place Seddon could have ordered a depleted Virginia brigade like Brockenbrough's to Culpeper Courthouse. The same could have done with certain brigades from other states. Rest and time to assemble absentees, recruit &c would have benefited commands that had suffered heavy losses at Chancellorsville. In exchange Lee would have larger brigades with him north of the Potomac, like those of Jenkins, Corse and Ransom or Cooke.

In a different light, consider Perry's Florida Brigade. The War Department waited until May 1864 to assemble various battalions stationed across north Florida and create the 9th, 10th and 11th Florida Regiments. Most companies assigned to these battalions had been organized a year or more earlier. More than enough were available to organize the 9th and 10th Florida Regiments in the spring of 1863.

A number of steps could have been taken to redirect available manpower prior to the summer campaigns of 1863.
Again, that's just my opinion.....