Here's a view of Custer from someone who fought under him:
"Brave but not reckless; self-confident, yet modest; ambitious, but regulating his conduct at all times by a high sense of honor and duty; eager for laurels, but scorning to wear them unworthily; ready and willing to act, but regardful of human life; quick in emergencies, cool and self-possessed, his courage was of the highest moral type, his perceptions were intuitions. Showy like Murat, fiery like Farnsworth, yet calm and self-reliant like Sheridan, he was the most brilliant and successful cavalry officer of his time. Such a man had appeared upon the scene, and soon we learned to utter with pride the name of -- Custer." [James H. Kidd, Personal Reflections of a Cavalryman, p. 130]
"Stars of the first magnitude did not appear often in the galaxy of military heroes. Custer was one of the few. The popular idea of Custer is a misconception. He was not a reckless commander. He was not regardless of human life. No man could have been more careful of the comfort and lives of his men. His heart was tender as that of a woman. He was kind to his subordinates, tolerant of their weaknesses, always ready to help and encourage them. He was brave as a lion, fought as few men fought, but it was from no love of it. Fighting was his business; and he knew that by that means alone could peace be conquered. He was brave, alert, untiring, a hero in battle, relentless in the pursuit of a beaten enemy, stubborn and full of resources on the retreat. His tragic death at the Little Big Horn crowned his career with a tragic interest that will not wane while history or tradition endure. Hundreds of brave men shed tears when they heard of it--men who had served under and learned to love him in the trying times of civil war." [James H. Kidd, Riding With Custer: Recollections of a Cavalryman in the Civil War, p. 131]