Maybe 8 was too large of a change, but I had my doubts about the maximum damage from charge with the increased speed. I spent the last few months playing all types of agility cav to make sure that such builds designed around high riding were still viable. Respec could have been handled differently, but at the time I was thinking that -9str and riding refund would've been too much. Could have just not refunded the riding skill.
I think the biggest problem right now is 0 leg armor for the horse. It makes sense realistically, but I think it should be a % of armor, not fully reduced to 0. Hopefully, the armor for the legs can be changed to the amount of armor on the horse / 2 or 1.5 or something. The intent is to increase the minimum # of hits to kill the horses (0 leg armor change, higher HP) while reducing the maximum number of hits (base armor on the horse). Many of the changes were internal so war horse doesn't have as much charge as large war horse, the very maneuverable horses have less charge than the horses that are centered on speed, and that there are no horses that are excellent at absolutely everything.
Hybridization as a whole is easier. Even 0 riding isn't *too* bad for pure melee, and many of the cheaper horses stats aren't inferior enough to never really use them when compared to those above.