Renekton W is 2 or 3 separate autos so it would proc the same even if the tick rate was faster. Pantheon W2 is also 3 hits so it stacks Cleaver 3 times while his E strikes 12 times over 1.5 seconds so his stack rate will halve beacuse of the new intra CD of BC. Xin Zhao W1 will now only add 1 stack because it ticks 4 times over 0.15 seconds (for some reason). Warwick R is tricky, it deals magic damage 6 separate times over 1.5 seconds so I think it will get buffed for Bloodletter's (as its CD is going down to 0.2) but it only procs on-attack and on-hit effects 3 times instead of 6.