1h cav is better in one thing,when you stop the other cav you can spam them and kill their pony,also ur weapon will hit first because of speed if you do it correctly.
Bad thing is that you need to go very fast with pony to one hit someone,and you need a lot of hits to kill other people horse without speed bonus.
About 2h cav it is good dmg,you can one hit other people,heavy horses if you get good speed bonus,you can kill stopped riders in one or two hits,but you can easily get shot because you don't have a shield.
Use bardiche,or that persian axe,you cant be more gay then that. 50 cut axe on horse,OP!