Yeah, 360 parries need to die. One thing I could say, light cav traditionally were just for scouting, flanking, and harassing. Making heavier horses (including their armor weight into that weight) more able to bypass parries either through additional bleedthrough and/or non-parryable trample damage would be good.
Mounted charges SHOULD 2-3 shot in almost all cases and even 1 shot in some.
The only problems I see with that video is:
1. Lack of Counters
2. Moving 10 feet from being fully stopped while turning isn't a charge. The movement physics there are horrible. Too quick to speed up, slow down, and turn. You should not be able to make sharp turns while moving any speed that gives a significant charge bonus.
If I run 10 foot on a horse while turning and you parry it, yeah it should be treated basically the same as if I were on foot.
If straight charge at full speed on a fully armored horse into anything but a wall of spears/polearms. Yeah. People should die. And you saw that in some of those kills he barrels into the back of some dude running away in a straight line. Those kills seem good. The mid-turn ones are a joke.