A lot of servers lately have been implementing CPS limits by blocking attack packets but as you probably know that doesn't change the velocity of a player due to velocity being a clientside thing. I know you have packets to change things such as missing hits on 1.8 and I'm sure you wouldn't struggle to implement something similar so servers can properly limit CPS
#CPS cap via packets
celest vortex
limber valley
r u suggesting to make everyone take more knockback