So far, I've never played a Legion-aligned character. The dialogue options are still in the game's files, just disabled in vanilla FNV. House playthroughs: One where I killed the Brotherhood and kept Veronica as a companion via an exploit, and another where I kept them alive and had House ally with them thanks to a mod that restores some cut content. I've done the NCR ending ONCE to see what kind of ending I'd get, and had the Brotherhood and NCR ally with each other then.
I generally favor the Brotherhood for their technology, and I mostly go for the Yes Man ending.
