Ironies abound. Custer didn't hate the Indians and they didn't hate him. He opposed the policy of forcible return to the reservations, testified against it in front of Congress, and nearly lost his command as a result. Major media darling. May have been the most photographed man of the 19th century. Had he lived he may have been the tribes' best hope at stopping the policy that led to the battle.
He does appear to have lost track of precisely where their forces were on his approach. Reno's movements were probably responsible for that. I would not categorize Reno's performance as a "betrayal" although he was court-martialed and several contemporary analysts did so. But certainly he also wasn't where Custer expected him to be.
The hill itself is a lousy defensive position but was probably the best one within reach by the time Custer did figure out what was really happening. But he'd have been flanked at some point unless he were relieved - the Lakota and Cheyenne had some of the best light cavalry commanders in the world at the time. Preventing that was probably why Keogh was where he was. That isn't obvious on a map but standing there it's pretty clear.
That's just my subjective and admittedly amateur impression. BTT for a great topic.
IMO, this tells it all. The history of the Indian Wars is fraught with second guessing. Custer did little different from other commanders in other campaigns. The biggest drawbacks to such tactics (in this instance) was the size of the villages, their proximity to one another, and his concentration of his wing on the bluffs as opposed to Reno in the valley. The bluffs and river divided his command beyond what normal tactics would allow. And it left him (and possibly Reno had Terry not showed up soon) with an indefensible position.
And, yes, it's a great topic.