How does giving US Grant command of an Army benefit me? I am still very inexperienced but since his Siege Expert, Master Logician and Good Sub Commanders traits only help units in his stack wouldn't he be more beneficial as a Corps commander where he will have many more combat units in his stack. I know he gives help to his subordinate Corps commanders, but is it really that much?
Another related question. In my current Union PBEM game Admiral Foote is eligible for promotion. Is there any benefit to promoting Admirals outside of scripted new traits or attribute increases at the new rank?