I am sure most of you are famaliar w/ Ultima Online. That was actually my first MMO and man did I have fun on that game. I was known as the great Agent Cherry! At any rate, they had a pretty neat thing for horsies. Basically every horse had a certain amount of endurance that would slowly recharge when you were walking the horse. When the endurance ran out, it would force the horse into a walk status which was quite slow until they regenerated some energy to run again. The trick was, this endurance bar was not displayed but you could get a feel for it if you rode the horse enough. It became especially tricky in those longer battles where it would kick off after you have exhausted your horse leaving you walking around at a critical point.
If we were to implement a mechanic like this where you can't just run a horse forever without it getting tired it might help balancing issues. Furthermore, I have suggested this before, a horse should take damage running into something that makes it rear up. It doesn't have to be a HUGE amount. Maybe around the lines of 20% making it so you really have to be on your game to ride a horse properly it may help with balancing issues. Riding a horse and killing people really should be an art worth mastering.
*Discuss*
-Love
Rainbow