Porter Alexander, Sherman & Grant all had good memoirs for the general officer. I didn't care for most other General Officer memoirs.
It is the work of the enlisted man that trips my trigger. In the shadow of the eagle, Si Klegg, Hardtack & Coffee, 4 years a soldier, An Illinois boy goes to war, Company Aytch, Citizen Soldier, A Business of War, Love & Valor, Hell & Gone, Seeing the Elephant, A bit of glory & a lot of hell, We are in a fight today, Drummer Boy's Diary, All for Union , A shade of blue, are all pretty good memoirs from the standpoint of the private soldier or lower ranked officer but my absolute favorite will always be Soldier Boy's Letters. Many are out of print but well worth looking up via interlibrary loan. A suprise to me were the various writings of Gov Joe Brown, they weren't so much memoirs as... well almost scholarly writings of the goings on in Georgia.
Another long out of print is To the last fool, it is a very moving and evocitive look at the war from a man who didn't want to be there, a conscript from near Birmingham Alabama IIRC. He touches upon the absolute terror of combat Vicksburg & Chickamauga in particular w/ details of the rout after Missionary Ridge, being wounded & captured @ Atlanta & his imprisonment @ Rock Island. His jaded view of disease & death as well as the slow realization that every man was "merely a dead man waiting his last dusk" is unsettling. WARNING: You CANNOT read this book w/out ending up horribly depressed & sad. IIRC the author worked on the Trans Continental RR post war and died all but penniless & stove up in the 1880's publishing the book in an effort to provide for his family. As the book had a rather limited run and was not a big seller... well you get the picture.