well, i like the idea, but this would require a whole new set of animations. and people would use this to move huge quantities of goods making prices fall.
Yes, a horse would be a good idea. However, like Gro'bul said, there would be a new set of animations. This idea would be possible to do, but it probally won't happen. It might be added in the far future. Personally, I like walking. Horses would be alright, but walking seems fine to me.
yes, the way they use in ogre island would be good, but i doubt horses have even the slightest chance in being implemented till we get a larger map. Because right now you can walk to the other side of the island easily.