@RiotRepertoir 2 cents from a Release Cassiopeia Main
2 Days ago @RiotRepertoir asked for ideas and clarity about what we think about her rework and general ideas about reworking her Kit rather then "Pls Buff Cassio!11!1!". I play Cassiopeia since Release and already wrote several detailed Post about her state and her rework.
So here are my Ideas about what could be done with her Abilitys.
If you Guys have Questions, feel free to ask :)
I´m super happy that we finaly get some attention from a Riot Dev who already aired some incredible reworks!
cries tears of happiness and joy 
Passiv: I would trade the CDR&Sustain&%AP for her old passiv. CDR has currently only an good impact on her Ult and the Sustain has % scaling which makes it only good in the lategame and feels terrible wrong in her kit. The community never liked the old passiv ( AP% ) anyways because you are in dire need of raw AP to make up for her bad (reworked) scalings, which all together felt like timed Gates and were unfun in general.
Q: Q should get the old numbers back and doesnt get empowerd by E anymore. Hitting a Target which has been hit by Q with my E should give a bigger MS Boost instead. Helps her Kiting and fits perfectly into her Kit.
W: Doesnt grow on its own anymore. Let it grow for every second that an enemy stands in it (Minions/Monster/Champions). Growing effect gets doubled if an Enemy Champ stands in it. Slow and Dmg scale with its size.
E:
Decrease the Dmg on her E... its okay... please take it... The One Ring
And let her E being cast while moving without having to stop like Syndra Q. ( Thats what you already thought about doing if I understood correctly which would be so extremly awesome! <3)
Again, helps her kiting and fits her Kit and would be a greatly welcomed change :)
R: Enemys looking at her should be stunned. Enemys who have been poisnd should be stunned even if they look away but for half of the stun-duration OR for the full duration but it should consume all current poisons. Enemys who are NOT looking at her and have NO poison on them wont be slowd anymore. Maybe shorter Casttime/Animation or bigger Range but thats not needed.
Hope you Guys had fun and lets keep this Riot Dev because he seems hyped and is willing to talk to us :) And he looks really cute <3