I feel like these should be an opportunity where if you perform well and manage troops correctly, you should be able to upgrade your army between grand battles. But even when after Antietam, I start hitting side missions where I'm like...ok i killed 10k of his troops, lost 3k myself, captured alot of goods, ok not too bad.....oh i only got 2500 troops for that mission. Then later on it's getting worse. As CSA I have to attack fully entrenched Union forces with no flanks, if there are flanks the only way I achieve it is by running brigades in a 4 man file between the union forces and the out of bounds or a river.
I just think, these should provide us an opportunity to do well and reinforce before our next big battle, not oh I completed all the objectives and inflicted 3x more casualites, but only gain half my troops back.