Actually heres my opinion. You guys are new...after a game or so you cant just post that the horses are too fast. I got in the beta at .500 and im a lancer most of the time when i play. Now from .500 to the current version (.613), i find that the speed of the horses are perfect and should remian that way...Now me being a lancer a lot and about going up hills, i find it perfect too, infact some spots on maps when you try to go uphill at a steep incline then your horse just stops. So thats actually good cuz in stead of slowing down the horse stops, and you start off slow again.. So i think they way they are is perfect..you just need to get used to them and you will think that they arent fast..
EDIT: and its actually quite easy to control them. I never hit anything at all unless some douche walks in front of me