, well does what it says on the tin by having horse calls, fast dismounts, talking/harvesting from horses, saddlebags, horse follow and a rather awesome menu for all that and more. Then you have UFO
which boosts follower amounts, allows you to customise default armour for companions, make them essential, check up on skills, teach spells, train, group commands, draw weapons in combat and not when you do and a bajillion other things besides.
But if your going to use UFO then take a peek at these other mods, Follower Trap Safety
which stops companions setting off traps and Move it Damnit
which increases the distance that companions move when being bumped into, helps in those narrow corridors.