[I would really like to know what others think about it or if im the only one who feels that way]
I played quite a few of Sivir as AD Caster in the past days and i noticed that all the lifesteal im getting is basically useless once someone applies grivious wounds to me, which happens super fast since im extremly squishy. They are usually meant to shut down champions that have alot of selfheal/heal and make it easier or even possible to deal with those. These Champions are mostly Tanks or build atleast alot of health, like Swain or Vladimir for example. I don't think it is fair for adc's or any form of squishy champion (except soraka) to get punished that much. I would suggest that the heal reduction would be based on how much maximum health you have. You would still reduce the selfheal by a fair amount, without punishing adc's/adcaster that much. It could be capped at the old 40% heal reduction. I don't know what they would need to do to not let soraka go skyrocket, but i feel like something has to be done. If not anything like the above, atleast reduce the time from the morrelonomicon until you are out of combat or the champion who applied those dies.