I can only speak for BM.
Its got a ton of utility. A beast to tank content in solo. Great damage. Rotation is fluid and easy to learn. Tons of beasts to go out and tame. Just a lot of fun. Which I can’t say for a lot of other alts I have. I have every class in the game besides priest at max level. The only class I would say is as fun as hunter would be shaman. But blizzard hates shaman more then their red-headed step child. So hunter it is! The Chad child!