About the horses, yes the Paso Fino's are smoother than a trotter, but there is still back motion, front-back, side-to-side and diagonally!  The super slow Fino Fino may be smoother, but I like progressing forward so I never tried to get my mare that collected.

You may want to try out a pleasure Tennessee Walking Horse (NOT a show horse!!!!).  I've never had the priviledge of riding a pure one, but one gelding I rode that was part TWH had the most amazing, long striding, smooth walk that covered A LOT of ground quite quickly!  Their temperaments are also supposed to be very good, calm and quiet.  As I said my Paso Fino mare was VERY fiery.