I find that the rules for mounted movement and combat as they are written in the CRB are unbalanced and unrealistic. As it stands now a rider can double move his mount, quick dismount and move twice more - essentially moving faster than a rider who stays on his mount for the whole turn. A rider on a war-trained mount can take a full attack for himself and for his mount (so long as the mount only takes a 5 foot step) with no penalty to the attack. This means that a druid on a mountain lion mount gets the full 5 attacks of his mount, and can still take a full attack. With the pounce feature of the lion, this becomes even more ridiculous.
There needs to be some measure of synchronicity between the mount and rider that restricts them from moving and attacking more than a single creature. I don't claim to be a master equestrian, but I can assure you that riding a horse is not a completely passive activity. Horses (and cats) do not hover across the ground when you are sitting on them. They jostle and bounce, and if one should decide to rear up and kick its front legs out, you need to be holding on with more than just your knees. Steering a mount so you can attack a target would also interefere with the mount's own attempts to bite/claw/kick at an enemy in reach.
In the issue of fairness and balance I propose that you institute a rule that makes manipulating your mount a move action. One move action by the rider would allow the full two actions of his mount. This would restrict the full attack action to just you or your mount (instead of both of you getting all attacks). Further, dismounting/mounting requires a move action from both you and your mount. You would still be able to do this as a free action with the quick dismount ride skill ability, but you have to remember that in order to quick mount/dismount you need to have a movement action available to use. This would prevent the exploit of double moving, galloping or charging then quick dismounting and moving even further on foot in the same turn.
With these rule changes mounted characters would still get the advantage of the mount's greater speed, as well as height advantage, trampling attacks, using your mount as cover and charging with a lance that is essential to mounted combat. Cavaliers, paladins and druids would still have some advantages when they are mounted, but in a more balanced fashion.
